My father who left us came back – what’s my Islamic duty toward him?

Assalamu alaikum, I’d really appreciate some guidance. My father walked out on us when I was 13. Now I’m in my late twenties. He recently returned to stay for a short while, mainly for health problems and paperwork. My mother allowed it, even though she still feels a lot of pain and anger – they’re divorced, so technically he shouldn’t be living with us since they’re non-mahram. I think she’s afraid to make him leave because he has nowhere else to go, and she worries about what people will say. When he visited back in September 2024, I felt overwhelmed with sadness and anxiety. All the bottled-up hurt just exploded. After he abandoned us, my mom had a terrible mental breakdown and nearly ended up in the hospital. Alhamdulillah she’s better now, but things were really hard – keeping a home, food on the table… I have siblings, including a younger brother who was only four when dad left. None of them have come to see him since he got here a few days ago. I’m the only one still living at home with mom, though we all live in the same city. To be honest, I’ve been pretty cold toward him. I barely talk to him unless I have to, and sometimes I just walk away when he tries to chat. I do that because I’m afraid I’ll explode and say something harsh. I know in Islam we’re supposed to be kind to our parents, even if they’ve wronged us, and I desperately want to please Allah. But I also don’t want to go back to having no boundaries and letting myself be taken advantage of – he’s done that before, asking for things. So what exactly are my Islamic responsibilities here? Is it sinful to keep ignoring him? Will Allah be angry with me? And how do I balance kindness with protecting myself? Any advice from Quran and Sunnah would mean so much. May Allah ease all our struggles. Jazakum Allahu khayran.