*hugs* I guess we can't change it at the drop of a hat
try for little things

have you thought about maybe, when he's tired/not in the mood, of a special activity that you can do together that's not sex?
something really special.
favorite activity? something he can treat you to? back massage? dunno
maybe ask him if that's a way to deal with it, so if he's not in the mood he can offer you a special activity instead to still shows he loves you