guy problems

so I've liked this guy for almost 6 months now. people say they think we used to/still do have a "thing"... I really like him but he probably doesn't like me back. he seems like the type who always has a girlfriend. sort of a player. also, there's a guy who has liked me for about 7 months. once, the guy I like said he was staying away from me to the guy who likes me... I sometimes wonder if the reason he "never liked me back" is because he's trying to be nice to the guy who likes me or if he's just a player and I'm misreading his flirting (which happens a lot, he even asked me to sit by him on the plane ride for a school trip.  I sat by him on the way but I promised my friend I'd sit by her on the way back home, so he sat with 2 girls...). also, the guy I like seems to have had a lot of girlfriends & once he liked my best friend, but it only lasted for like 3 days & he didn't like her anymore. what do you all think?  is he a player/did he like me earlier but not anymore/is he hiding his emotions because his friend likes me???  thanks!!