There is such a thing as tacit or passive consent. I think this is not a big deal and should not be blown up out of proportion. I certainly would not persecute the other kid.
There is a lot of sexual experimentation among young boys. You are probably unaware of it, but a huge proportion of men have had isolated juvenile homosexual experiences. This lone event should not scar your life. You can dwell on it if you want, or look for blame, but that is not productive. Move on.
I would like to throw my two cents in and cry 'CONSENT' there's nothing wrong with two 12 yo boys fooling around, or two 8 yo girls. IF THEY HAVE ALL CONSENTED. Initiating sexual contact with someone without asking first (while the person is sleeping) is TOTALLY NOT OK! NO matter what age or gender either of you are consent is the golden word. I would say that this is a concept he clearly didn't grasp, as dead bodies by nature of their lack of ability to consent, are off limits.
I would not worry about having 'enjoyed it'. This is one of the key features of guilt that keeps children from speaking out. One of my favorite arguments regarding this: Man says to Lesbian "What's the difference, if I shave real smooth I can go down on you and you won't even notice I'm a man" Which is technically true (I know I'm going to get yelled at for this one, forgive me laddies). Sensation is sensation and if it feels good, do it. But humans have brains and if you are not mentally turned on (have not CONSENTED and are pretending to sleep) than it's wrong. The fact that you enjoyed it is irrelevant, you didn't CONSENT.
I hope that you find a therapist you work well with.
Yes it was abuse. the same thing happened to me between the ages of 5-15 with a male "friend". It's hard to understand it as molestation, because it's so cloaked in lies and denial. But make no mistake. Two 12 year old boys should not be engaging in sexual activity. There's something unhealthy there. And if you're hurting because of it, go to a therapist. I've been to one and it has helped me cope. Don't get discouraged if the therapy doesn't help right away or if the therapist isn't good for you. Try another therapist until they're helpful if necessary. I promise it gets better.
It's my opinion that anytime anybody performs a sex act on you without your permission, it's abuse. Plain and simple. It sounds as though now as an adult he may be into some pretty weird stuff and I would hope he's not doing this to any children. I would talk to somebody professional about this if it is now interfering with your adult life. It's not your fault, you didn't do anything wrong, but it still can have bad effects. Good luck to you.
I'm kind of confused about the ages here . . . were you both 12 years old or were you 12 and he was an adult? Please clarify.
Yes, it is still abuse. It doesn't matter what the person's age range is in relationship to yours. So long as it wasn't consensual (which the fact he started while you were asleep and unaware and therefore couldn't say no would imply), it was abuse. Not to mention, it made you feel "violated, humiliated, scared...." Sorry this happened to you!