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You have them.
Clearly, it wasn't working with either of those two guys, that much is obvious from your letter. It was never going to work. But because you're afraid of being alone, you're torturing yourself about it.
The pain is natural. Don't fight it. Don't expect to feel better tomorrow - you'll only disappoint yourself. Just take things one day at a time. Read a good book. See a play (no Ibsen!). Reconnect with some old friends.
A lot of people on here are making fun of you for over-thinking your problems, but I think that this over-thinking is a defense mechanism as much as anything. Dealing with your emotions organically can be a real challenge to some people.
Just focus on yourself for a while instead of focusing on dudes. Being in love is awesome, but it has it's drawbacks too, and one of those drawbacks can be losing sight of who you are. So enjoy the solitude. Get to know yourself better. If you do that, it will be much easier on you when the right one comes along.