I've been there. Am often still there. Sundays in particular can be rough for me. I can share how I've dealt with it.
My antidote, or one of my antidotes to anxiety has been structure. I've tried to build it into my weekends. I go to yoga on Saturday mornings, then go to Starbucks to journal, then get groceries. Then I have a 12 step meeting then I go to the gym, and that's Saturday. On Sunday I go to a Unitarian church I like, then I sit with a meditation group. Back to Starbucks. I journal a lot. Then chores around the house and yard. Then another workout and a movie, and that's Sunday.
Planning is an excellent weapon for me in my battles with anxiety. Open time has been a real challenge. If you build some type of regular, routine activity into the weekend, it helps a lot. Drinking, well, that's a whole other post, I won't nag about that. As to the rickety stool, I know how that feels too. The only thing I'll say about that is it takes away any chance you have of becoming well. Permanently.
It took me a while to set things up this way, I had to be patient. Now weekends are sometimes even rejuvenating. Don't give up. See a shrink if you aren't already. Know that you are not alone. We're right there with you.