Leah,
Pretty sure I've replied to another post of yours, so I will try not to repeat myself, but I am in a similar situation. I never imagined I would feel this way afterwards, either. I guess you have so much hope going into the process that this will be a life-changing event for the recipient. I, too, have thought about other people that I could have helped instead, and also worried that someone I care about would need a transplant, and I would be unable to help.
I really do try not to think about it (I'm sure you do, too) and remember that I did what felt like the right thing, but I admit- seeing the recipient is incredibly difficult for me. As is trying to not feel any emotion when I hear about him being in the hospital. I don't want to become a bitter person. I'm sure you don't want to, either. If you can, stop seeing your recipient, and stop asking for updates on her. It will only hurt you. I've mainly managed to do this, but I do run into him sometimes.
I'm trying to come to some kind of peace with the situation, but it's very hard. I wonder if maybe it isn't healthy to read about all the wonderful experiences people on this site have had, but then again, I appreciate that this site provides a wealth of knowledge and support. Still, I rarely come on here, and I think it's because I know I'll start thinking about my experience, and I try to avoid that as much as I can. I hope we can both find something positive from all of this. I've thought about talking to someone about it (as in a counselor or therapist or whatever) but I haven't done it. I wonder if it would help. I've also thought about writing about my experience (maybe in a fictional way, so I have some distance) to help get some closure and move on. I haven't done that yet, either. I'm sorry I can't be more helpful, but I definitely understand how you're feeling.
-Annie