Missing the Libido

My boyfriend and I are 30 which basically means I'm horny pretty much most of the time and his sex drive has nearly dropped off the planet. We finally did end up having sex last night but it was after not having sex for 2 months and after I complained enough about it. now before you suggest that I should come on to him to get things going, believe me, I do. about 80% of the time he tells me he's too tired. I know he's tired because he works long hours, but when we were in our early to mid 20s I had to beat him off with a stick even when he was tired, sick or in pain. I guess my question is, have you experienced this sexual lull in your relationship and what did you do to get his mojo going? Hypnosis? lol I'm kidding, but I really am interested to hear others experiences.