This is a bad moment. There will be more. There will be good moments. There will be stable moments. Lots of them. You are not alone. Not only the mentally ill have bad moments. Every single living human is going to have a mixture of all of the above. We keep going through the bad moments to get to the better ones. That's everybody.
I have studied history extensively. I am always amazed that even in the most horrible of circumstances, life long enslavement, generational religious persecution, etc. there are always accounts of the good moments that occurred even in the worst of times. I choose to focus those moments of positive, rather than the horror.
You mentioned two good moments in your post, cuddling your kids and seeing your therapist. Maybe try focusing on those moments and trying to make more moments like those happen.