controversial topic....

I recently had an experience where I was extremely drunk and I needed a place to sleep. I had a trusted long time friend, we hung out all the time and I trusted and valued him as a person, and had never given him any inclination that I saw him as anything other than as a brother
he said I could sleep at his place and he would sleep on the couch.
The next morning, I woke up naked in bed with him and no recollection of what happened the night before. I was scared, confused, and upset. A friend of mine said it was considered as rape, I need more opinions on this and I would love to know your thoughts. 
EDIT!!: due to the comments, I forgot to mention that he was sober and I was drunk.