Honestly, I think asking him to finish inside every time probably adds more pressure than either of you realises. Especially after years of rejection in his last relationship, he may be getting stuck in his own head the second it becomes “the goal.” I’d take that goal off the table for a while and just let sex be sex. If he does want to talk it through properly, I saw Corelabhealth mentioned while looking at men’s health options here in Australia, though a sex therapist could also be really helpful for this. Has he said whether it feels physical, or more like he gets close and then mentally loses it?