@Rose76
Although I have lurked these forums over the past few years I only recently joined.
I felt compelled to reply after reading your despondent post.....I have read many of your previous posts also.

Everybody has their breaking point and it seems you have reached yours.
Looking after your SO seems to be a thankless job and spiralling you into a deep depression.

It’s time to take care of you. You will be no help for him if you are not healthy yourself.
Seems like he has sucked the life right out of you. It’s time for his children to take over where you going to leave off.

You will fall deeper and deeper down the depression rabbit hole if you don’t take the time to take care of you.
If you can’t find a psychiatrist who can see you right away....start by doing something simple..like a 30 minute walk daily. I know that seems like an insurmountable effort seeing as getting out of bed is near impossible.
Force yourself to get out in the sun and move your body.

Join a support group for spouses taking care of their SO. Strength in numbers, it’s always good to have others to listen when they know exactly what you’re going through.
As far as a stimulant medication....it would really only be a band aid if it even helps and in many instances once you come off of them a deep depression can set in.

A few ailments that can have a profound affect on your energy levels and exacerbate depression...
Low Vitamin D levels
Hypothyroidism
Menopause
Low iron( that you have been treated for in the past)
Sleep apnea
Lack of exercise
Nutritional deficiencies
Low B 12 levels
Stress
To name a few...

Does your local hospital offer drop in programmes for depression ?
Sharing what’s on your mind with others will make the burden of depression easier to bare.

Taking care of yourself is the first step to pulling yourself out of this funk.
Make the effort...you’re worth it.
If you don’t take care of you...nobody else will.
HUGS ....��������