Your difficulty with martial arts sounds like it's mostly because that particular martial art doesn't agree with you. There's an immense variation in the styles of martial arts, and it's very important to try several and find the one that works best for you. But then you said you've been doing it for about 10 years, so you probably know that.

You sound like you would benefit from one of the ones that puts a lot of emphasis on pair work, like Shorinji Kempo (it's quite obscure everywhere except Japan). It does have katas, but not many, and they all have pair-form versions, which helps with figuring out why you're doing each particular move.