Having doubts about my LTR boyfriend (25M) and I (23F) long term.

We were friends for a year until he gave me an ultimatum about three years ago. (Date or not see each other.) I love him, so I said yes. We moved to go to school and started living together (I know, my bad.)

We recently moved back to our home town after graduating. Even though he’s 25, I feel like he wants to be an adolescent again and spend a lot of time with his guy friends without me. I’m starting my graduate program and am ready to seriously settle down and think about marriage, home ownership, and children within the next five years.

He’s my best friend and I love him, but if we met now, I don’t know if I would choose him. We come from different backgrounds, which I initially didn’t care about.

At risk of sounding snooty, my family and friends are highly educated and professional, and he is a first generation college grad without exposure to that atmosphere. It’s not a status issue for me. I’m just worried we have different visions of what adult life looks like.

He almost said as much: “I feel like I’m 25 and you’re trying to be 32; sometimes I feel like you’re my mom.” Ick.

Positive traits: he’s steady, honest, kind, loyal, and makes me feel safe. He makes me laugh all the time and is my best friend.

Negative traits: he’s not as ambitious as I am, doesn’t prioritize health in the same way, and is not a “life long learner.” He and his family really like to drink as a hobby and I’m trying to permanently quit.

Are there vetting questions I can ask this deep into the relationship? I’m sad :(

TLDR: are there questions to ask 3 years into a LTR?