I have OCD. I have had it since I was a teenager and I'm 52 now so I think I do know a lot about the disorder. Having said that, everybody's OCD is different. What I get stuck on you may just pass over without a second glance. Some people have germ OCD...I don't. Some people perform rituals while other have the "Pure O" form of it which is irrational thinking. Some people have a combination of both. And yes OCD thoughts do seem real and we do recognize them as irrational but we just can't help ourselves and stop ourselves from going to the dark side...unless we learn how to deal with the thoughts. That is where a psychologist comes into play.
Nope, God and the Universe is not telling you to go vegan. It doesn't work this way. What is happening is you have a chemical imbalance in your brain, a neurotransmitter imbalance, that causes you to get "stuck" on thoughts. While the "normal" person may think the thought and let it go, you think it, over analyze it, and finally catastrophize it. So please do eat meat. Eating meat is not the problem...it's the pesky neurotransmitters in your brain. You can retrain your brain and the way you think by learning cognitive behavioral therapy from a psychologist. That is your best starting place. Can you see someone?