Assalamu alaykum - Need guidance about family pressure to give my ex another chance

As-salamu alaykum. I’m a divorced Muslim mother of two young boys and I’m under a lot of pressure from family to give my ex-husband “one more chance” as a father and maybe as a husband again. I wanted to ask for Islamic perspective because I feel overwhelmed and don’t want to make decisions just from emotion. My marriage was arranged. I said no at first but later agreed to please my parents. From the start it felt one-sided. He was distant, lied a lot, and had a serious gambling problem that put our family at risk. One of the worst moments was after my emergency c-section: I was still in hospital and he took my bank card and gambled everything away. I couldn’t even pay for parking or buy basics for the boys. That’s when I knew I had to leave for my own safety and for my children’s sake. Since the divorce he shows up in short bursts, promises to change, plays father for a few weeks, then disappears again. When he vanishes he blocks calls or ignores messages. I’ve never stopped him from seeing the boys; all I’ve asked for is proof that he has steady work, a stable place to live, and that he’s getting help for gambling. He has given none of that. My eldest has been hurt by this instability. He asks painful questions about why his dad can’t be reached or keeps breaking promises. His school is worried and he’s in therapy now. I can see how it shapes him and it terrifies me. I’m trying to protect him from feeling abandoned or unworthy. Recently my family invited my ex to a religious family event without telling me. I was told only older relatives would be there, so I let the boys go with uncles. Hours later I learned their dad had turned up and the boys were excited to see him. I wasn’t consulted and I would not have sent them if I’d known. I feel betrayed because I know how much it will hurt when he disappears again. Now family are pressuring me to let him babysit while I attend the women’s program the next day. They say I should go and “enjoy myself” and give him a chance. But last time I trusted him like that he took my car to buy medicine and disappeared for a month; my brothers had to look for him in casinos. Still I’m told to forgive, to “sacrifice for the children,” and that I’m being too harsh. I’m afraid of the slippery slope: if I agree now the next steps will be more access, overnights, and eventually talk of getting back together. They already say he’s “trying to change” and expect me to trust his words though his actions show nothing. He also has an older child from a previous marriage in another country. During our marriage I was told he couldn’t contact that child because the mother prevented it; after the divorce I learned he simply chose not to be involved. It’s a pattern of leaving when fatherhood is hard and returning when convenient. I don’t want my sons trapped in that cycle. I’m not against sincere repentance or forgiveness. I believe people can change, but change must come with proof and steady behavior - not emotional pleas at family gatherings. I feel accused of being bitter when I’m trying to protect my children. So I ask: what does Islam say about this situation? Am I wrong to require evidence before trusting him again? Is it permissible to refuse even if family insist “do it for the children”? Am I sinning by setting this boundary? When does sabr become enabling harm, and how can I explain this to relatives who expect me to endure everything because I’m a mother? I don’t want to act from anger, but I also don’t want to give my children’s hearts back to someone who’s already hurt them. Any Islamic guidance, practical advice, or support is welcome. May Allah reward you for reading. JazakAllahu khayran.