Hugs. Just wanted to let you know I've gone through a very similar journey and really understand your struggle though thankfully I got sick as a child so didn't have to worry about work and looking after the kids.
I had unexplained arrhythmias chest pain dizziness and exhaustion for about 10 years before they finally worked out the correct diagnosis which for me was postural orthostatic tachycardia syndrome. Turned out it was only discovered shortly before I was diagnosed and it's only recently they've worked out any treatments that help. I saw so many doctors and had so many tests. Many doctors decided I was making it all up or that I was nuts because they couldn't see what the problem was. Almost all of them just gave up.
I really hope you get a good diagnosis soon and they can treat you! Best wishes
You may want to look into dysautonomia. What I have is one kind and I think ehlers danlos is connected with dysautonomia so maybe it will help with finding the right tests.