The fact he thinks you’re “judgemental” because you prefer being honest (“have the moral high ground”) is a red flag to me. If being with an adult who lies like this isn’t acceptable to you, the sensible thing to do is split up, rather than try to train him to be more honest. It may seem minor on the surface, but lying can get really insidious.
I certainly wouldn’t want to raise children with someone I found myself arguing about my fundamental values on a regular basis.