It appears to me that you are working from a premise that is highly flawed. One problem is that you seem to assume that the party is the reference frame, that if conservatives and the GOP are separating it is because the conservatives are running away. Me, I'm pretty much right where I always have been. If me and the GOP aren't on the same continent these days, it doesn't mean that I went anywhere.
The other, related, issue is that you seem to be assuming there was ever a connection in the first place. Again, just talking about me here, I have voted R in the past because it just so happened that they were the least worst candidates, not due to party loyalty.
The GOP can do whatever it likes. If it wants to go after the moderate vote more than it wants the conservative, that's its choice to make. But my vote belongs to me, to use as I see fit, and the cost of those moderate votes may be running a candidate that I will not support. If there is "running away" going on, it's not me that's doing it.
This statement places you in the camp of the independents (even if you are registered as a rino).
So...my question remains....if you vote on a "case by case" basis (may I assume conservatism holds most of your interest?), then what national candidates do you back? Given your assumedly conservative views, you and those standing with you (including myself if my assumptions are true) have precious few office holders for whom to vote.
And...unless we can elect a majority of conservative - and I mean real conservative - candidates, we will always be marginalized....and the nation will continue on the path upon which it has set it's feet.