My wife has epilepsy. She's had it since she was a baby when she fell off of a bed at 6 months old and suffered a TBI. It was very bad for several years. Back to back seizures and often went into status epilepticus. They slowly became more infrequent until she had her last one at 11 years old.
She beat the odds, graduated high school and overcame a lot, which is pretty amazing since her original prognosis was that she'd never be able to walk, talk, or go to school, and certainly should never have children. Tell that to our 27 year old son.
She was doing very well, then when our son was 7 her seizures returned when she was 35 years old. At first it seemed like a one-off, but over the years they increased to the point where driving just wasn't safe for her anymore and her independence was drastically reduced. They're mostly controlled now with meds, but she still experiences mild absence seizures 2 to 3 times a year. Just often enough to not clear her to drive. I know what its like for a loved one to be afflicted with this disease. Its awful. There's more to it than just occasional seizures.
My wife met someone at work who also has epilepsy and lies to his dr about his seizure frequency just so he can keep driving. Long story short, he moved on my wife and fueled her resentment over her loss of independence (and her awful, controlling husband who didn't want her to drive) and they had an affair. So I also know what it's like to be on the receiving end of that as well.
I'm sorry you've found yourself here, but this is a really good group of folks who understand what it is you went through, and are likely still going through as far as the fallout goes.
Friend, it sounds like a you rugswept your wife's affair. Have the 2 of you really talked about it at all? Does she understand the trauma she inflicted on you? I know your d day was a long time ago, but betrayal trauma is real trauma, and if left unaddressed it can fester for years. Sometimes decades. PTSD symptoms are common and triggers can come out of nowhere. How are you doing right now?