Short answer: Yes, there is too much focus on this relationship to make you happy.

I know this because I have done the same thing, and some of the things which you mention here I identify with completely. I totally understand the jealously aspect because I would feel the same way in your situation. However, as an outsider looking in, I have to say that I do not feel that it is fair for him to have to put his friendship with someone he has known for so long on the back burner for you. When you want a relationship with someone, and you care for someone, it means that you take them as they are which means that you have to accept their people too. I'm not saying if he was friends with someone unhealthy you couldn't have a say or whatever; that's beside the point. I think you probably get what I mean.

I don't really have much other advice to give you, because I tend to put all of my eggs into one basket too quickly as well. But the problem with this is that you're cruisin' for a bruisin', so to speak. All I can say is that you have to find a way to go with the flow, to find other things to focus on besides him, to make it so he is not the only source of contentment and happiness, or it is too easy to feel hurt by things...like when he pays attention to his female friends.

Good luck.