My mum ‘F48’ has ended things with my step-dad ‘M53” how do I ‘F25’ support my mum?

I don’t really know how to start this off, I’ve never thought of reaching out on here to ask with these situations, the thing is I’m going through a tough time myself but still I want to be able to support my mum.

So they have been together since I was 8 however they have known each other since children themselves.

My step-dad is terminally ill, COPD, 36% lung capacity with oxygen being at 82% he is dying. Told that he would be on palliative care before Christmas. He needs at home oxygen but can’t have it due to still smoking. He has made his decision to no quit and says he won’t give up something he enjoys if he ain’t got much time left anyway.

Now my mum has accepted this, she doesn’t argue with him, she attends his appointments with him, she gets his prescriptions, she makes sure he takes his meds and his inhalers etc however I don’t think he realises this, how much my mum loves him. Now my mum has had 9 children and the younger 5 children, who she still has to ‘parents; are 16 and younger plus she takes care of my brother ‘M21’ who is mentally disabled (has mind of a 9yr old child) too. She deals with EVERYTHING! Now when she become really ill she still showed up, she had her gall bladder taken out and still pushed on, idk how she does it, I’m immensely proud of her. When she was ill my stepdad never went to appointments with her, essentially to put it bluntly my mum had to care for herself and the children but had no support in doing so.

I spoke to her today and she broke down on the phone (it takes a lot for my mum to show emotions like that), she said she’s told my stepdad she doesn’t want to be with him anymore. Obviously he still lives in the house as he has no where else to go, my mum says she wants to up and leave everything on him and see how he deals with it all. She won’t as she wouldn’t do that to the children but she says it out of frustration which is when she is really struggling.

Whilst she’s been dealing with this she has supported me through the ending of my relationship with my ex partner. She has been focusing on herself too and lost a lot of weight, she goes on daily walks by herself, she is into her fitness which is why I think she’s been able to cope so well.

It’s a lot for her and I see her on Thursday too.

I love her so much, she’s such a role model, I’m trying to follow her for her strength, in my own ways though. I just don’t want to mess up supporting her through everything she’s going through.

Any advice at all?