The best thing to do in these situations is not to place such high expectations on yourself and that person, as you could be setting yourself up for disappointment. I'm not saying something wonderful couldn't happen, but it puts a lot of pressure on you and that person to say that he could be your Prince Charming.
I think what you should do is not only get therapy, but also get a journal for your thoughts about yourself. You obviously feel as though you aren't worthy of love, but are desperate to be with someone in order to feel important. The thing is, you ARE important - whether you get with this guy or not.

These feelings you are having make you feel vulnerable, which why I suggest the journal thing. I've felt desperately in love with someone and even contacted them when they showed interest, only to have been rejected for what I recall now as myself simply being desperate for companionship of any kind. Approval that I am attractive. In other words, I was going about it for all the wrong reasons.

Give yourself a break, and talk to someone before diving into a relationship and write down expectations you do have for yourself and another person you'd like to be with. The best thing you can do for yourself is claim YOUR worth - with or without a man.
Good luck to you.