Oh Holly, I wish I had some words of wisdom that would make you sigh with relief and say, "Of course! That's the solution!" I think my hardest times have been the "mental" part of the physical hard times--having MS slap me in the face and say, "Hello! This is the way it is now!" Or at least, FOR now.
I don't mean that it doesn't get better, because (so far) it mostly has. Sometimes the relapses or worsening of symptoms settles down, sometimes I've found ways to adapt--not always my first choice, and sometimes I've had to learn to live with the "changes". Read "changes" as "losing something else".
It bites. Most of the time I'm able (eventually) to count my blessings, but I don't go easily into that dark acceptance of loss.
Wow, I'm cheering you up, aren't I?
I know, cheering up isn't the point. I hope above all that this valley will soon be behind you and you'll see physical improvements. I hope that, until then, you're able to find ways of coping and adapting--even if you have to bring your family along kicking and screaming. They'll adjust.
Only you will know when "I can't do this anymore" becomes literal, and which "this" has to change. That's been the hardest for me by far. For instance, I didn't want to stop working, and I couldn't AFFORD to stop working, but I couldn't do it anymore. I don't know if working part-time is an option for you, or taking some LWOP--I'm sure you've already thought of every opition.
Can you hire a cleaning person once in a while? Can you (ugh, I know) ask a friend or family member for help, at least until you have time to catch your breath and take stock?
I keep repeating myself, but there has been nothing harder so far than looking at 100 spoons' worth of things I HAVE to do, and knowing I only have 40 spoons, no reserve tank. Especially when the people around you that love you the most are saying, "What the heck is a spoon?"