Why did he do this? And why do guys do this

This guy i used to like, and who used to like me too, is being f***ing weird.

He sent me a snapchat (if anyone doesn't know what it is, its an iphone app where you can send pictures to people that lasts 10 seconds tops with or without text) of him and one of friends that are girls, kind of leaning on him, WTF!

he used to just send me ones of just him, and that was fine, but WHY send one of him and another girl!

why do guys even do this at all?! To show off! It disgusts me, especially since i had feelings for him.

Btw, we weren't fighting or anything, we're still friends, so its not like a revengeful picture or anything, it was just so random.

I then text him "no", and straight away he replied "no?" but I didn't say anything back, he really didn't deserve to be spoke to after sending me that picture.

WHY guys, WHY?

Well, maybe he wants you to get jealous. He thinks you will like him more if you see that other girls are on him. Just forget about him. TRUST ME. There's better.

Sometimes guys really are oblivious when they do things like this. Maybe he was just sending you a picture of himself. I don't know. I'm sure he didn't think that it was going to bother you as much as it did and he's probably confused. If you guys "used to like" each other and now are "just friends" then don't worry about it.

If he is playing games, then just don't give him the satisfaction of acting like you care.