How to get him to want me?

So there's this 'friend' of mine and we hook up every so often and we used to talk like every night but recently it seems like he's not interested at all. I know he doesn't have a new girlfriend but his ex has been on his back about him talking to me (I'm 5 years younger than him- 20&25- so it's not illegal or anything she just thinks it's weird) but it's happened before but we never stopped talking but he's blocked me on Facebook and not texted me or anything. I've messaged him a few times in the last few weeks but he hasn't replied and I don't want to seem to pushy. 
He used to be all over me and invite me over like every week but now he's not even talking to me and even if I bump into him around town he smiles and sometimes hugs me. I just feel like he's not interested in me anymore but I miss our friendship more than anything. Am I being too pushy? Should I just give him some space?