Sociopaths don't worry about being a sociopath. By definition, people like that feel nothing about hurting others. So the fact that you worry about it proves that you are not one.
Your fears are terrible. OCD can really be awful, but it's just OCD. There are two treatments for it which can help you defeat it. One is medication; the other, which is even more powerful, is cognitive-behavioral therapy. It generally only takes a few weeks to work - and many, many people with fears just like yours have gone on to lead happy, peaceful lives. Believe me - what you are frightened of is very common, and it is very treatable. If the treatment you've received so far hasn't worked, you need to find an expert, someone who specialises in treating this sort of thing.
Don't hurt yourself. Think of it this way - this is a battle which you can win. Don't give up before the battle has even begun. At least give it your best shot, attack this thing in any way you can. This is an enemy, and even though it seems very powerful, it isn't. With the right techniques, you will look back upon yourself later this year and you won't even be able to BELIEVE that you had fears like this. Honestly - just give it a few more months. So much is at stake - remember how you felt before this started? You can feel like that again.
Don't take OCD's crap any longer. Don't put up with it hurting you like that. Take the fight to its home turf. The only way you can do that is see someone who is an expert in treating people with OCD. Go to www.ocfoundation.org and look at the referrals section - they can tell you who would be best suited in your area to treat you. Treatment is actually surprisingly easy - you will see that, to your own surprise, these fears will stop bothering you very quickly.
If you really think about killing yourself, call 911 or go to an emergency room. That will make it clear that you really cannot stand this crap any longer and you will get help quickly. But don't go down that road. There is no need to. With the right treatment, you will get better and feel normal again.
Please e-mail me if you would like to talk.
Straitye