Should parents financially support an adult daughter that’s is not financially stable?

My husband has a 24 year old daughter who has a 3 year old daughter and currently pregnant with her 2nd. Not in a relationship and the guy she’s pregnant by now wants her to get an abortion. However, she is telling my husband she might not ever get another opportunity to have another child because she has a cyst on her ovaries. I don’t know much about that. My husband has been supporting her financially but it’s taking out of our household. I think the part that really frustrates me is that I am the one already taking care of 90% of the bills and his money is being spent on her and well being and whatever he wants. So now, another child coming into the picture. Like I told him once before as long as she can get money from him she not applying pressure on the kid’s father for them to step up so he’s actually putting money in their pockets. Am I looking at this wrong or selfishly?

I’ve tried talking to my husband about it and the moment I go toward that direction he gets upset. Saying everyone wasn’t raised like you or know how to get thru life the same way as you. I told him that’s crap because our son who is 15 now was 2 years old when I graduated college and went on to have a successful career by working my butt off all awhile I had no support from him at the time because he was incarcerated for 13 years. His daughter didn’t maintain contact with him. Never visited him and now that he’s working all of a sudden the past few months since he has been working she’s trying to establish a relationship with him. I don’t know if he’s doing it because he feels guilty for not being there but she’s grown now with kids. Also, let me include that while he was in jail I would send her money for different milestones in her life like report cards, high school graduation, moving into her first apartment and holidays. She has not reached out to me at all since her dad has been released and during the whole time her dad was incarcerated. I kept trying to get her to see her brother - our child and that didn’t happen until he got out and that was 1 time. She hasn’t tried to contact her brother since. Somehow with all of this he seems to be oblivious…I don’t know. At this point, I’m considering to walk away from it all as I don’t work my butt off to be taken advantage or unappreciated by anyone and I feel that way. Like I helped him get on his feet with starting his own business and now your concern is on others. Like I get that’s your child but she’s grown. He’s paid her car notes a few times, paid for granddaughter birthday party, and given money. However, he has not once paid any of car payments on my vehicles that he has driven multiple times even though he has his own truck. Like I’m frustrated beyond relief. Then he says, your financially okay so what’s the problem. That’s not the point. I’m ready to let 18 years go at this point honestly. My kindness has been taken for weakness and it’s affecting my attitude and moods towards him.

What the best approach on the next steps?