Hi Op
I can totally get your at wits end,
I would do a compromise that suits both of your needs,
Your husbands cuts down reduces how many nights he spends at karate,
He just attends the karate classes he teaches at,
So he supports you more, and or you have trustworthy family member or a good friend or a reputable paid mother's help babysitter services to help you,
It's unfair on you especially at this stage when naturally your baby 👶 is going to be Needy,
It's natural to feel being a first time mom especially to feel over whelmed ,but obviously you need to surround yourself with as much support as possible,
Your husband priority should be towards you and his new baby ,family,
Obviously both of you still need to retain your sanity and identities, you both parents but individuals aswell,
Hence its healthy to have a balanced way of doing stuff,
Such as you having outside interests, hobby ,meeting up with friends at a cafe for a catch up ect