husband not really into sex, tips, advice?

Let me start off by saying my husband is really amazing. Funny, smart, handsome, patient, kind the list goes on. We have been married for four years and together for eight and he's never really been that into sex. I have decided to stay because of all the other things he is (see above list) but I'm reaching a point in where I'm not sure any more. We haven't even kissed in a month! 
I've tried everything, outfits, inviting others into the bedroom, toys, any sort of kink you can imagine. I've tried vanilla, romantic style sex. If there is a flavor I have tried it. While I try he is really into it he just never tries or initiates once I stop. 
Is he lazy? He isn't gay or bi- I've tried that (all manner of kink) he enjoys sex while we are having it we just barely ever have it. 
I don't know what to do. I can't talk to anyone about it and I feel so damn lonely. 
Any advice would be greatly appreciated!