To understand the true nature of the divide, you must understand that the EP is not the Eastern pope. Orthodoxy is very clear, in that the faithful are to uphold the purity of the faith.
Maybe that is why we seem to be fragmented. We separate from apostate bishops, as the Councils tell us to do.
Some of the separations are from human sinfulness; others are required for fidelity to the Truth, such as the Russian Church Outside of Russia, off the Red revolution.
It is simply maddening to any well-educated pious Orthodox Christian to hear Latins and Uniates assert that there is no doctrinal difference between Rome and Holy Orthodoxy. The Orthodox regard unity of faith as the test of communion: if there were no difference in faith, we would be in communion with Rome.
It is also quite annoying to hear the North American and Western European condition of adminstrative disunity in violation of the Holy Canons--an affliction which resulted from the Bolshevik Revolution destroying the links to our mother patriarchate--universalized. In most countries of the world, there is administrative unity under a single hierarchy (in Africa, for instance, the Patiarchate of Alexandria and All Africa, in Russia, the Patriarchate of Moscow, in Japan the Autonomous Church of Japan,...).
I will lay out the doctrinal differences which separate your communion from the Church briefly, indicating what I view to be the import of each:
The insertion of the additional clause in the Creed is baleful in two ways. First it is theologically unsound, representing a confounding of the eternal and temporal, the created and Uncreated. The Latins' explanation that the second procession refers to the temporal mission of the Spirit, which takes place through the Son, does not undo the conceptual imprecision of using the same verb--not even two occurrences of the same word, but a single word--in the Symbol of Faith to refer both to the Eternal and Uncreated Procession of the Holy Spirit from the Father, spoken of by Our Lord, and to the temporal mission of the Spirit in coming upon the Holy Apostles and dwelling in the Church to "lead [us] into all truth". This confusion is then the root of other errors, both ecclesiological and soteriological.
Second, the acceptance of a modified Symbol of Faith, in defiance of the decree of the Holy Ecumenical Council of Ephesus, and the definition of the change to be no change represents the decisive departure of the See of Rome from the mind of the Church, both ecclesiologically and theologically. Once the Symbol of the Faith had been accepted and the Arians and pneumatomachians defeated, even heretics like Nestorius and Dioscorus did not presume to tamper with it. It is only by holding a theory unknown to the ancient and undivided Church--the theory that the Pope of Rome in his office and person is superior to the Holy Ecumenical Councils--that the Latins can claim that this is not a departure fromt the Faith. It seems to be generally forgotten in the Western use of 1054 as the date of the Schism, that Rome and Constantinople were out of communion over precisely this issue since either 1009 or 1014 (depending on whether the acceptance by the Popes of Rome of the heretical clause became known through the publication of the still extant coronation rite of the German Emperor Henry II, or the no longer extant election encyclical of Pope Sergius IV) at which time the Popes of Rome were removed from the Diptychs of the Great Church of Constantinople because they had cease to confess the Orthodox Faith.
It is only in the context of the confused pneumatology of the filioque that the Latin insistence on having a human "Vicar of Christ" become understandable. The demotion of the Holy Spirit represented by both subordination to the Son and the confounding of the Spirit's activity with created things leads to the desire to have an intelligible principle for the unity of the Church other than the indwelling of the Spirit--hence the Latin shift from the conception of unity of faith to communion with the Roman Pontiff.
That the modern Latin conception of the Papacy is an innovation unknown to the ancient Church is well-attested by the canons of the Holy Ecumenical Councils, which attibute a primacy of honor to the See of Rome on the basis of its position as Imperial capital (the basis for precedence among sees on the basis of the status of the city is also demonstrated by the fact that the Jerusalem was suffregan to the Ceasarea for centuries, despite its undoubted Apostolic foundation, and the fact the Alexandria ranked ahead of Antioch, even thought Antioch was founded by St. Peter himself, while Alexandria was founded by his disciple St. Mark the Evangelist), and provide certain narrow appelate jurisdictions to the Pope of Rome--narrowly drawn powers which would make no sense at all if the Church had regarded the office in the way the Latins do since the Schism. (The schism between Pope Nicholas and St. Photius the Great resulted from the Pope overstepping his authority: while Patriarch Ignatius has a right to appeal to Rome, the Pope had no right to judge the case personally--the Holy Canons provided for the Pope of Rome to appoint a commission of metropolitan bishops from neighboring provinces to judge disputes between bishop, not judge the case himself.)
The innovation of papal "infallibility" only widened the gap between the Latin understanding of the Church and the ancient and catholic understanding preserved in the Holy Orthodox Church.
Created spiritual gifts are unknown to the Orthodox. Grace is the Uncreated Energies of God--God Himself acting--or it is powerless to save. Again the Latin notion confuses the created and the Uncreated as regards the activity of the Holy Spirit.
This confusion is also evident in the Latin conception of purgatory: a temporal fire (or state--they downplay the fire aspect now) which is part of salvation, cleansing those passing through it of their sins. The Fathers knew of no such state--the Holy Scriptures speak only of Paradise and Hades, while the Fifth Ecumenical Council, in condemning the vain opinion of Origen, Didymus the Blind and Evagarius Ponticus that the torments of Hell are temporal, not eternal, did not mention in contrast any temporal purgative torment. There is only one fire--the Eternal Fire--which the Fathers tell us is the love of God. Again purgatory, with its temporal fire, confounds the created and Uncreated, the temporal and the eternal. It is, of course, well-known that abuses connected with this error--the sale of 'indulgences'--were the occasion for further schisms and heresies to arise in the West.
The second Marian dogma--her Bodily Assumption--is a matter not domatized about by the Orthodox, although we believe on the testimony of Holy Tradition that after her death the Theotokos was bodily assumed into heaven. The mischief of the Latin dogma comes from its "legislative history": those who advocated it includes a fair party who held (and still hold) that Mary was bodily assumed before death. The papal proclaimation of the "dogma" was deliberately worded so as to allow this position--quite contary to Holy Tradition--to continue among the Latins.
Coupled with the IC, a bodily assumption before death becomes a stumbling block to sound understanding of our salvation: without "Original Sin" and deathless, Mary would have a pre-lapsarian Adamic nature, not the human nature common to us all. A Christ born of such a "pure vessel" would not assume our nature, and as the cry against the monothelites said "not assumed, not redeemed." Mary's nature must be like ours completely for Christ to redeem our nature by assuming it, so too, her will and her activity or energies must be identical to our own. The failure to exclude the "assumption before death" position in the papal proclaimation must, thus, be seen as a modern day return to the position of the heretical Pope Honorius--a blank incomprehension of the basis of our salvation.
I will not go into the symbolic critique of azymes, nor set forth the myriad other divergences in practice which have accumulated on the Latin side--from laxity in fasting to "lay Eucharistic ministers"--which would impede reunion. The divergence in the practice of prayer, however, seems rather important, since as Evagarius Ponticus told us before he wandered off into error "the true theologian is he who truely prays, and he who truely prays is a theologian." (Another divergence--in the West, theology seems to be synthetic science, for the Orthodox it is a positive science.)