Every single person we meet, we can find a aspect about them, and ask;
' What if ...? '
What if he is a work-a-holic and I never see him ? What if he moves ? What if he decides he wants babies ? What if,..what if,.....
I find it best not to think like that unless there is a blatant, obvious issue at the forefront that can hold you back, together as a couple.
I`d suggest having a open talk with him, and deciding wether you think this guy has his Big-Boy pants on. Is he capable of living as he feels is fit, ..authentic to himself ?
No relationship is guaranteed anything,...what matters more is if you feel you can handle yourself. Are you prepared to enjoy the relationship for what it is, and what it has to offer, and letting the cards fall where they may ?