So sorry to hear you're going through such an incredibly tough time. It can be so frustrating when you know something's not right and there just seem to be no obvious answer.
About 6 months back, I had reached the brink of absolute despair. My GP is a legend who ran a number of tests and sent me for a few due to the fact I had virtually no energy. I was convinced it had something to do with my B12 levels (seeing I have shots for this) but blood results actually showed high end of normal. Getting off the couch was a challenge on top of memory issues and things were only getting worse.
In the years preceding, I'd actually developed an interest in energy itself. As a lay person in the way of understanding, I'd accumulated books on Prana, quantum physics, epigenetics and so on. By the way, I'm far from an academic genius, so all were a pretty basic read. Don't know what happened but one day it hit me 'It's about the energy'. So, bamm, off I started on quest to simply build and play with energy.
If you're interested in this energy angle of things - basically we're energy. Our cells vibrate at different rates. The faster they vibrate, the more energetic we feel. When we exhaust our energy in a number of ways (mentally and physically), various systems in us slow down. As naturally energetic creatures, there are a number of natural ways to speed things up. We're hydro powered - so getting enough water in us to feed our cells is a must (preferably filtered water without chemicals). We're solar powered - Vitamin D is a biggy in the way of well being. The list goes on. You might even consider talking to a dietician in the way of food and energy. Some foods are natural energy boosters and some either give us little energy or require a lot of hard work to process.
What makes a big difference to the start of the day for me personally involves stretching exercises. Typically, we don't just jump out of bed in the morning raring to go. We stretch. Most folk will naturally give a single stretch but the benefit of continuous stretching for all parts of the body is incredible. Try it and notice how many times you yawn. Letting out relaxed energy helps boost mind and body. Our body will do a lot of things naturally, a lot of the time without us even noticing. Picking up on subtle cues as prompts to expand on those cues is highly beneficial.
If you're up for a fascinating read in regard to how we tick, 'Becoming Supernatural' by Dr Joe Dispenza is truly stunning.