Honestly, the first thing you need to do is get on top of your mental health. It’s good that you’re seeking treatment - I know how hard that step can be. Don’t give up on that yet. If your treatment isn’t working, talk to your care team (doctor/therapist/whatever) about trying something else. The first meds I tried made me super sick. I was lucky that the second thing worked well with minimal side effects. Everyone is different and has different needs. There are tons of different med options out there.

Once you’ve found a treatment that works, you’ll be in a better place to make decisions going forward.

If your mom is the disabled person (ie, not collecting a spouse’s disability payments as a widow or something like that), there is no means testing to qualify for SSDI payments. The disabled person is disabled, and qualifies for payments, no matter how much money/assets they have.

If your mom has enough cash on hand to buy a house, how is that any different from owning a house? Assets are assets, regardless of what type they are.

Not OP, but I am considering doing a limited purpose FSA in addition to maxing my HSA for the coming year (it’s open enrollment time). I need an eye exam, and need a bit of dental work done, which I could use the FSA for. It will allow me to use pre-tax dollars to pay for that, while still allowing me to take advantage of maxing my HSA. Basically, it just provides me additional pre-tax space to save money. Since I know I will spend those dollars regardless (with no FSA, I would pay out of pocket, and leave my HSA invested), it makes sense to contribute to a pre-tax account for those expenses.

I do agree that an HSA is “better” in general, so if you’re not able to max your HSA and pay expenses out of pocket, there’s no need to do the limited purpose FSA.