Does he want a serios relationship or is he using you?
The real problem with this question is that by overthinking you run the real risk of chasing away the good guys, attracting the bad ones or misinterpreting a breakup as him using you.
Sometimes, good guys show some behaviors typical of players who just want to use you. Other times, you’ll find a guy that does all the things an A+ boyfriend would do, only to find out months later that he was stringing you all along.
Point is, it’s impossible to have a 100% success rate figuring out if a guy is serious about you or not. Sometimes you’ll get burned, sometimes you’ll chase away the serious guy who just can express himself properly. You have to make peace with yourself that sometimes you’ll make the wrong choice – and that’s ok.
Another thing to consider is that guys will try to use you in more ways than just physical intimacy. Some guys use you because they’re lonely or bored, and you’re an easy way to pass the time until they meet someone who they think is “better”.
Other guys will be caught up in weird emotional dramas and they’ll use you to make their ex girlfriend (or even current girlfriend) jealous, or as a way to “get even”. Other times, you’ll be caught up in a rebound relationship while they get back on their feet.
He might even use you is for the money, or other practical advantages like having a place to stay.
And as painful as it may be, in case of a breakup you have to consider that the guy was serious in his intentions, but ended things because he believed the two of you weren’t compatible in the long run.
Taking all of this into account, how can you tell if a guy wants a serious relationship, or is just using you? As a rule of thumb, watch what he does, not what he says.