flying you were scared to talk to him about a relationship ending problem because he was feeling tired last night and it would have ended up as a row.
Sounds awfully like you were carefully managing yourself to avoid setting him off, to keep him happy, when you were feeling so so tired of it all, last night.
You knew that he would not do the same. He would not manage himself to keep you happy when he was tired.
This is you two in the easiest stage of your life. You catch up on sleep at the weekend, two incomes, no kids, easy to look after property, mortgage easily manageable, careers on the up, plenty of time for hobbies, work late whenever you want, healthy and young.
Yet he can be too tired to be nice to you. You will have to talk to him about what will happen when you have children. That is so wrong. He is the one who is behaving like a brat. He is the one who should be thinking about how he wants to behave towards you. He should be thinking about how to change his behaviour. He should be the one thinking about how it will be when he has children. He knows he is an arse when tired, everyone on the planet knows parenting means exhaustion, so he should be thinking and planning and telling you how he plans to manage himself.
If you have to push him to consider any of this, if you have to "have a talk" about his behaviour, that indicates very clearly that he does not see his mistreatment of you as a problem that is his problem.
What would happen if you stopped managing his behaviour?
You know, expect him to be an adult, expect him to speak to you with respect and kindness at all times, call him on it immediately if he doesn't, don't think carefully about whether he is in the right frame of mind to act like he cares about you if he needs calling on something.