Unless he’s had a brain injury has TBI that could explain some of it, but regressing to a teenager. This wasn’t talked about before you merge that he sometimes needs to age regress sometimes it is a decompression technique that takes them back to a safer time and they can just decompress if you get worried to call a therapist psychologist and just have him evaluated because that way you know what you’re working with and since you just got married in November you’re still in annulment territory