I'm 22 and I've been seeing someone I really like for the past 4 months, we met after days of breaking up with my ex.

this guy, he's 25, we get along really well, we have crazy chemistry, we can talk for hours about everything and anything and not get bored, he makes me feel like the prettiest girl in the world, but he's still hesitant about the concept of marriage, haven't told his family about me because he has some problems with them and, is still studying so he doesn't know where he would be in the next 5 years so it's harder for him to include me in a future he's not certain about

my ex is 29, he has a good job, loves me so much, told his family about me and introduced me to them, wants to get married to me, his future is stable, and knows where exactly he sees us in the near and far future, but I don't enjoy my time with him as much as I do with the guy I'm talking to right now, doesn't make me feel as pretty, and don't get along as well too.

now my ex's older sister contacted me wanting to talk to me and I know she's going to ask me to get back with her brother and I need to make a decision before I get back to her.

I'm afraid that I'll regret not getting back to him once the guy I'm talking to leaves the picture since he's not as serious about me as my ex is, but I know for a fact is both of them were proposing right now, I'd pick him over my ex any day.

please help, I know no one can make this decision for me, but any insight is highly appreciated

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