Don’t let him waste your TIME.
Your TIME is valuable and though you may think that you are “young enough” and that you have a lot of it left, think again.
TIME stops for no one.
If commitment, children and/or marriage is what you want, don’t let him drag you along for 10 years if your limit is 2. Decide how much TIME you are willing to give the relationship but keep it to yourself. He doesn’t need to know about your time frames are. If he really wants you, he knows what he should do.
And don’t stay with him just because you have “invested” years in him and don’t want to start over with someone new.
It’s better to start over now with someone better for you than to stay with him and be miserable.