Treating mold can be difficult and slow. Have you identified the source of your exposure and removed yourself from it?
Because mold suppresses the immune system and MCAS can increase your reactivity starting with these may make treating lyme a bit easier but I might consider starting on some treatments to reduce inflammation, cytokines and organ support at this stage if you can tolerate it.
Do you know what approach your functional doctor is planning to take? Have you had a chance to read Neil Nathan’s book Toxic?
I like this link as well on an herbal approach to CIRS (I’ve been treating lyme and co and mold with herbs)https://youarethehealer.org/mold-and-toxins/moldy-people/healing-from-mold/step-by-step-protocol-to-heal-from-mold/
There are a few members here dealing with MCAS as well as mold so they may have some suggestions.
Sorry for a ton of advice when you’re really just needing to vent.
Living with invisible illness when no one around you gets it is one of the hardest parts of the illness for me. I found it was so important to me to have this group where everyone just understands. I gave up explaining to people and I just say I have chronic illness if it needs to come up. No one ever asks for details ;-)
Things will get better but it can be a long slow recovery. I found it was really important for me to keep my expectations low and find different ways to participate (I have kids so I had to do lots more quiet stuff with them and less active things).
I think that was more advice. Warmest hugs and I hope today is better.