I think that your feelings seem real, I really do. But I guess it depends on what you define as love...
For me love is something that emerges over time, as you get to know someone. I am afraid I am with your friends when they tell you that it's not real love because you don't know him. I think you're in love with the idea of him and not the reality, which is something you have to be careful with because nobody can live up to our fantasy and you could get very hurt over this one day.
I don't want to hurt your feelings here, and I certainly do not want to belittle what you feel because lust and obsession are very strong feelings - but I don't think it's possible to be in love with someone who you do not know properly.

I think what you're feeling is totally ok, providing it doesn't become an obsession or last too long. It's ok to fancy someone like mad and think about them, but I think you perhaps need to seek some help if you become too attached or it makes you feel too bad because you're not with him and that he has a g/f. You admit that you naturally have an obsessive personality, so perhaps looking at why you are like this is the answer.

Hugs