Well PerfectlyFlawed, I like your title. I believed I was defective for a very long time, that I somehow was responsible for all this stuff that seemed to happen to me, around me. Perfectly flawed. Defective in some way. Later I learned PTSD develops when a normal person (adult or child) is required to survive and abnormal situation. It wasn't me that was defective, it was the situation.
We did well, we survived the challenges of a dangerous, abnormal situation. Now that we are beyond the dangerous, abnormal situation, we discover we don't know how to act in a more or less normal situation, plus we have these intense feelings buried in us that keep intruding, keep messing everything up.
So, naturally from your perspective, you looked for a safe person to experience normal (non-abusive) sex with. Safety is a big concern to us. And when you acted on your felt needs it turned out badly because the person you perceived as safe was, in the normal (non-traumatic) world, in a committed relationship.
Our challenge is to learn to behave appropriately in our current (beyond the trauma) situation, getting our current needs met by participating in a set of relationships and activities appropriate to the new us (at least for me the person that came out of the hostile environment was very different than the person that went in) in our new, more or less normal situation with all the really intense thoughts and feelings from the old (traumatic) situation constantly being triggered and screwing up our perception and judgement in our current situation. Or something like that.
In general, if we focus on participating in appropriate activities in our current situation in appropriate ways appropriate relationships will develop. Learning to live better with PTSD takes a lot of effort, and a good therapist to help us sort out old stuff and current stuff is helpful.
Take good care of the person who survived ;)
Ted