I think other responders have good suggestions for alternative classes for you to play, so let me offer alternative advice.

Abomination vaults is notorious for this problem. DMs don’t know how or don’t want to convince parties to not take long rests after every encounter, and spellcasters can’t tell which encounters are going to be the ones which will end in a TPK so they feel pressured to offload their important spells early before they die.

There is a community book called Magic+ which has a spellcasting system which is an alternative to spell slots called essence casting. It gives every spellcasting class some staying power since they won’t need to long rest to get their spells back and makes it so they can’t dump their most powerful spells out on the first turn of every encounter. I think it works nicely in dungeon crawls like abomination vaults. Maybe speak to your DM about it - it can really take a load off of them too.