Homosexual tendencies are not a sin - it’s the homosexual act that the RC church has issue with.
Priests are supposed to be celibate anyway - so maintaining their celibacy in the face of their homo/hetero sexual inclinations is the rule.
Let's say that I know a fellow church member that is attracted to the same sex. He has asked for forgiveness and does not act out his inclinations. Still, I hate him and tell him he's a terrible person. I may even go so far as shunning him and wishing he would get out of the church. Who would be in the wrong?
RE: Homosexual tendencies are not a sin - its the homosexual act that the RC church has issue with.
In short — Love the sinner, hate the sin.