Why is he being like this?

One of my guy friends is being really annoying lately. We used to be sooo close and we'd talk every night on xbox but now it's like once a week. It started after me and my friends went camping and he was there and we were forced to share a duvet and he kept trying to hold my hand but i just kind of turned over because i didn't want to lead him on. Also, he tried to get close to two of my other friends on the same night. When we do talk though on xbox he's always bringing up other girls..."ooh sophie better be online, yes she's online!!" or he'll have been out with his friends and there will have been girls there and he always obviously wants me to ask him about it, but i cbf asking just for him to talk about girls i don't even talk to. He just brings up all these random girls all the time that i didn't even know he was friends with. Oh and on msn just now he was like "omg i'm on an ipad" so he obviously wanted me to ask "did you get one?" just so he can say "nahh it's sara's". Why can't he just say it's hers in the first place. he doesn't really talk to any of my girl friends anymore after camping, it's just me but only a little. I know it's not jealousy or anything because i've rejected him in the past but one of my friends he was trying to get close to liked him at one point so i feel bad for her about it... i just don't understand why he's being like this. any ideas?