How to not completely fall apart when “rest” isn’t an option?

Single parent of an 8yo and a 4yo both with complex needs. As the title says, rest isn’t an option; at least not the amount of rest I need for the amount of pain I’m in. I have lots of other neuro/skeletal diagnoses but I think the fibro exacerbates it all so I’m asking here.

I’m not actually sure how long this flare has been going for. Months, a year?, maybe with some days here or there where I’m feeling ok. But between all the daily tasks of mothering (including not having enough sleep at all in the last 9 years), and then having to do my best to stay “fit” and active for the sake of my body, dragging myself to appointments, running errands, helping friends and family who need it etc. I just can’t handle it emotionally.

I need help, ways to mitigate the pain so I don’t burst into tears every other moment. I’m sick of the depression this causes. It’s not even depression, it’s pure exhaustion. Feeling like I’d rather not be here at all if it has to be in this much pain, which is a horrible feeling when I really love my life and know how lucky I am to have the wonderful things I do.

I’d rather avoid the topic of medications just because I have a complex history with them and it’s something I’m working through with my team of doctors anyway, but is there physical/mental/spiritual/environmental changes I can make? I wish I had a full body heat pack. I’d wear it everywhere I went.

Other parents with fibro, how do you do it? I’m so tired of letting my kids down because my body is letting me down.