is he using me??

i've been seeing this guy for about 6 months, we don't see each other often because he's at work and i'm at uni. we used to text a lot, but now we text less than once a week :/
i understand that he's busy and so i don't want to bother him by texting him all the time.
but whenever he has time off work he'll text me and ask if i want to meet up. and whenever we do meet up we end up doing "stuff" lol

i know he has lots of friends who are girls, and sometimes i feel like he's maybe more interested in some of them than he is in me. i don't want to be that annoying girl who tells him to stop talking to other girls and give me more attention, but sometimes it really annoys me.
this sounds immature, but it pisses me off when he likes and comments on other girls' pictures on instagram.

i'm the type of girl who is really good at hiding things and showing that i don't care, but obviously i do, i just don't want to say anything because it makes it look like i'm obsessed with him. and that's just creepy.

is he just using me for his own sexual pleasure?
i don't understand guys, they say they want a girl who is chilled out but it seems as if they enjoy being with a clingy psycho girl more.

This depends. When you say you're 'seeing him', does this just mean you fool around? Or are you actually going on dates, getting to know each other etc?

If it's the former then yes, I'd say he's using you. If it's the latter, if you aren't officially a couple he can post and comment on whatever he wants (although tbf he can still do that once you're together as long as it's not emotional cheating). Maybe try going out together and not just messing around every time you meet up.

And you can always straight up ask him if it's purely fwb or if he intends to take it further

i'm only seeing him.

i can't be bothered being in a proper relationship because they are sooo much effort.
maybe i'm just paranoid