What's his deal?

So I've been having a rocky relationship for the past year.friends, not friends,friends again..an so on. we have known each other a long time but tried to start dating a year ago but couldn't get along, mostly because i always ended up feeling played by the guy ( he has admitted in the past to ignoring me on purpose to get a reaction) I'd confront him which would end in us falling out. So this time we fell out I have met someone else an he went back to his ex..all is good we are now just friends, only randomly a week ago he gets in touch knowing i'm with my boyfriend at 11pm ,saying sorry not been in touch ..how are you!! seeing as it was late i left the reply till the next day, saying yeah no worries, everything is great doing really well an so forth only to then get quite a ****ty short answer, i made a joke about about how talkative he was, for him then to say sorry im busy i promise to talk more soon babe..What the heck..he got in touch with me!! Then to top it all off he's now started to post pictures on a public social site of his girlfriends breasts an things an using silly captions I've said to him in the past, I'm confused as to what's going on am i being naive in thinking we can be friends?? Thank you for anyone's thoughts on the matter.

i'm far from an expert in relationships, but it kinda sounds like he was horny that night and probably remembering previous relations with you... Next day he was over it...