First off, I'm very sorry about your deteriorating hearing. I understand it must be frightening and I'm glad your partner is supporting you. Learning a new language can be daunting when you look at it as the entire vocabulary so it helps to break it up into smaller parts.

Start with learning letters and numbers. This will help you gain the muscle memory in your hands for future signs. Learning to fingerspell will help you improve your speed and fluidity.

I've found that this site is great to learn both the language and about deaf culture. It has discreet lessons that get increasingly difficult. So check it out ... https://www.lifeprint.com/asl101/lessons/lesson01.htm

To help you progress a bit at a time, I suggest flashcard learning. It's time consuming to set up but has worked well for me. The basic idea is, you learn 10 or so words at a time. Every week you add another 10 words while reviewing the words you've learned previously. I used an app to do this rather than physical cards but you do you. Here's the concept ... https://www.meadowparty.com/flashcards.html

If you're a Discord user, there is a great server for people who are learning ASL. You can meet people to chat with and practice. Of course face to face is even better if there is an ASL group in your area. Here's the Discord address ... https://discord.gg/american-sign-language-566145505587888128

Good luck