Why would you think that?
Social conditioning of women has too much to answer for.
Why would you feel sympathy when you are fucking exhausted and your partner makes doing his share in the marriage and caring about you seem like a chore. Leaving you stuck picking up his slack.
Let me guess, he's also one of those losers who thinks the home and children are mostly your responsibility?
Was the second kid planned? Because I think you aught to think seriously about whether or not you want to stay with this man(child) now, before you're too knackered from raising two kids to leave.
You have a young kid, a difficult pregnancy, a recent family illness, mental health struggles, an unsupportive husband who seems to think caring for you is a chore.
You're not the selfish one. Women aren't work horses you know.
Your well has ran dry. And you can pour from an empty cup. That's not selfishness. Its exhaustion. In part it seems, as a result of his selfishness.
But you need to stop sleepwalking through your life and making it harder for yourself with more children.
For the time being, make plenty of cups of tea for you both. Then once he's recovered from the shock of his mum's potential illness, you need to have a serious chat with him about how you need him to step up as a partner. Hiw you realised you felt resentful that he hadn't had your back through your father's illness yet, now the tables have turned, it's shown you how little he cared and that's making you realise the relationship is in serious trouble.