I think you should get therapy, seriously. If it's affecting you so bad you're suicidal, you need to get help. There may be things you're inherently doing "wrong", and not realising it. (not necessarily your fault; could just be how you're raised, or just from lack of experience) I agree with hvert's post in its entirety. To summarize:

1. Get some professional help, ASAP.

2. Ask friends/family what you may be doing wrong, or something that gives off a bad impression.

3. See a doctor and I personally would recommend that you avoid prostitutes like the plague, but to each their own.

4. Perhaps start working out, if you aren't already. Lots of women seem to have a thing for muscles or at least a toned body. (as has been my experience, at least) If you're a bit messy, lack manners, etc, then it's worth sorting that out... from what I gather, women like a guy who's polite and "well-groomed", or at least makes an effort towards how he looks. I'm not judging you, because I haven't the foggiest what you're like, I'm just echoing the kind of crap I've heard or read online, and.. well, I suppose common-sense. You wouldn't wanna date a woman who lives in a toilet, would you? xD)

5. People keep saying that you have to get out there, do things where you can meet other women. Get involved with something you enjoy, and see if you meet anyone.

6. I love the idea of asking your friends to set you up with someone; could be a nightmare, but could also work well.

Best of luck.

PS
If it's any consolation, I'm 28 and have been in 2 serious relationships. I've been single for 3 or 4 years, now, following a heavy relationship that went to "feces". At first, I just didn't want anything to do with women, I didn't want to open up, I didn't want to get close, and I didn't want to be vulnerable; it still applies, but it's applying less with every day. I admit, I'm lonely, ... I miss "love", but, the way I see it, the more I get my crap together and mend the mess the past left behind, the better my chances of not only meeting a woman, but coping with a relationship, again. Also, I was about 22 before I got into that first relationship.