First of all, welcome. I understand your sense of comfort - the friends who I feel most comfortable around are my gay friends - they don't judge me.
I think the trick for you is to look at what behaviors YOU are doing that may precipitate their leaving. Now, there WILL be the fair share of people who DO abandon, but I would suspect that there is probably some behaviors that you do to push people away. It's almost like a self-fulfilling prophecy... we feel that we are unlovable, so we behave in such a way that those around us will PROVE what we believe. I hope that this makes sense and please understand that I'm not criticizing.
I don't have the abandonmnet issues, but I do have a long string of broken relationships throughout my life. When I get too close to someone my first instinct is to do whatever I can to sabotage the relationship. Now, this is completely on a subconcious plane - as much as I desperately want the love, the understanding, the compassion, the fulfillment of a loving relationship, I start to find faults and in the end, it justifies my wanting to end the relationship.
IMHO, I think that this can be applied to pretty much any aspect of our lives.... whenever we see a pattern, I think the first instinct is to blame everyone else when most times we should be looking inside. At least that has proven true for my life.
I hope that at your next appt. (or before), you will let the doc know about the reaction to Prozac. It is well-known with that drug in particular that it can force manic behaviors to the surface. And, it obviously bothers you, so it would make sense to try another anti-depressant. There's a ton of them on the market, so you're not just stuck with Prozac. You deserve to have a decent quality of life and not have a medication that's supposed to help you actually knock you down a few steps.
There are no unresolved issues - they just didn't resolve themselves the way we would have liked. "Grinder and Bandler - Neuro-Linguistic Programming"