I have autoimmune disease. In my case it is RA and I've had it for about 20 years. I too had a bad case of mono in high school and so did many others with our problems. So here are some ideas for you and take them or leave them :)
I am in many fb groups for autoimmune diseases. Some are natural and some are ok with all the drugs. In either case, I am in the groups I like for the support. This is not easy and no healthy people want to hear how tired it makes us to try to brush our hair or take a shower. I would be lost without my groups.
I used to take every drug known to man for about 12 years. I got off them when I lost "half my size" because I figured my new smaller body needed a reset. Those drugs were very hard on me and led to a lot of secondary problems. Now I take very little and try to control this with food, rest, exercise, and positivity. (So easy!)
I eat the aip way for the best health in my case. When I am strict, I do better. This is basically organ meat, fish, other meat, bone broth, vegetables and coconut oil. I uses things like turmeric and ginger as staples. Very exciting but it works for me.
At least know your anti-inflammatory and inflammatory foods and eat/avoid as needed.
Yes, this definitely goes in cycles and you do better if you act accordingly. If you need to rest in bed for 3 days, do it. Don't worry about what anyone says, and just do it. But get up and exercise gently every few hours and eat and drink well as best you can.
As far as cleansing, you need to do this carefully. I do Dry Skin Brushing and wrote two books about it on Amazon. Here is the first one and chapter one is for free to read on both of them.
https://www.amazon.com/Brushing-Ready-Detox-Softer-Fresh-ebook/dp/B00KVV3PUA/?tag=viglink23646-20
The main point I would make is to really clean up your act for a month or more before you do any cleanse. You can get rid of a lot of toxins that way and then the cleanse will not try to kill you. I went in blind the first time I started Dry Skin Brushing and it really for horrible for 10 days. Now I love it and will never stop. And after that I have does some other cleansing protocols and they were not so bad or hard on me.
I will stop talking here now since this is so long. I can go on for hours more :)
Best of luck, keep trying, and trust in God to protect and keep you safe.
Thank you for this wonderfully long and thoughtful reply. I eat similar to you it sounds. I will write your tips down and go over them one by one and see which ones help me. I'm very thankful for you sharing your experience like this. I'm unfamiliar with dry skin brushing but will absolutely look into it now.