Awww... I'm so sorry you're having such a rough time! You are DEFINITELY not alone. We OCD-ers are definitely out there, and we all struggle. Isn't it great to be able to find others like you? Makes me feel a little less certifiable at least.
I used to worry about vomiting too, and then when I finally did vomit once my worry was just obliterated completely because it really wasn't half as bad as I thought it would be. It was on a date, and I had to run to the bathroom and I just lost it. Afterward I was like, "That was what I was so worried about?"

It's like "What's the worst that could happen with this?" But OCD does not always follow such logic I know.
Have you done any cognitive-behavioral therapy or anything? Have you ever considered taking a vacation from your OCD? That's my favorite strategy for coping.

Sometimes when I am just mentally out of control I am able to recognize that "Hey, if life were REALLY as bad as I feel I would expect molten lava to be flowing into my apartment. Since it's not, MAYBE it's OCD and my body's anxiety response is just WAY too loud and it will go down if I 'take a vacation.'" So I recognize the OCD episode for what it is, and I give myself permission to step away from it and say "Okay, I will come back to this later. Tomorrow at 3, maybe." And sometimes the anxiety subsides enough that I don't have to come back to it. Sometimes I find myself calling my therapist.

Ha!
Anyway, you're not alone. At all! And if you can, rest and relax and give yourself permission to go on a mental vacation!
- Captain OCD