Wow, this is a bit of a different situation to be sure. You say that he is a loving and kind father when he is with them, but has no interest in them when not involved with them. That is indeed a bit confusing to say the least.
As a father of three children myself, they are the most important blessings in my life. I love them dearly and cannot imagine not being with them, even though they are now grown children themselves.
What I am wondering is if this whole thing has less to do with being ABDL than perhaps psychological scars from the failed marriage. Could it be more of an avoidance of the pain and situation that he was in that is manifest in trying to avoid anything that brings these things back? As you say it appears he is loving and caring for them when he is with them, but then out of the situation he seems to avoid these opportunities. This could be somewhat due to an avoidance of even being with his ex-wife during the exchange and so forth. Or perhaps the trauma associated with the previous marriage causes even thoughts of it to cause him to regress to his ABDL self.
In any case, there are some psychological issues here that really should be addressed. Perhaps a counselor or psychologist might be able to help him work through the emotions he has. An ugly divorce and/or marriage can create the same sort of PTSD as other traumatic events, and perhaps even more so as it involves the person you loved and shared your life with. But the thought of avoiding perhaps some of the greatest treasures in life (one's own children) because of some psychological issues is really sad. And one that I am certain in the future he (and you also) will regret if you don't seek out the opportunities.
If indeed this is something to do with his needs for being ABDL, I think that is even more sad. I hope this is not the case. I am ABDL, and in my experience never was this in any way connected to my children. I worried before having children about the fact that I liked diapers and what it would be like as a parent with children in diapers. But there simply never was any connection between the two. When my children were in diapers, I simply took care of it like any other parent and my own diaper interests actually seemed to fade away during this time. Perhaps it was because this was certainly not a pleasant chore, and I was grateful when each were potty trained. So at least for me, being a parent and caring for my children in diapers had no connection with my own ABDL desires. They were two different and separate worlds.
While I know everyone is different, I simply can't relate to someone avoiding their own children because they themselves are ABDL. I am sorry for saying this, but if this is actually the case, I think your husband really does desperately need help --as his priorities are in the toilet and his actions are very selfish indeed. It is disconcerting to me, and I am sure to you, that he even would insinuate that he is avoiding being with them because of his being ABDL.
I hope this latter situation is truly not the case, and that the real cause is what I suspect might be the case, in that he is avoiding memories and the pain of his previous marriage.
However, in either case, this is something that mere friendship and even your companionship is likely not adequate. While I am not a fan of psychologists or psychiatrists, I believe the investment in seeking their assistance would be well worth it in you and your husband's situation.
I wish you the best and my prayers go out to you and your husband (and his daughters) as you sort through these things.
