I find your story interesting. I cannot say I have all the answers, but can give you a few thoughts from experience.
- No marriage is perfect, and no one person can give you everything you desire,..... Even in the darkest moments, I know that ultimately, if I left my spouse, it would be because circumstances said I had to, not because I wanted to. If I didn`t possess that ultimate feeling of 'wanting' the person, then I would know it was over. Sure there are the many times I feel the need to be alone, and away, and to not have my spouse near me, but something still keeps me anchored.
^^^ With those feelings, comes the fantasy of being invested in something new, and refreshing. The reality for me, was that a poly relationship felt like double trouble. An extra spouse to deal with. So all the pressure was doubled. Be cautious on the poly investing you do, if you think there might be a potential that you were interested in it as an escape. I think 'timing' is everything, and self-awareness. Unlike some other advice, I DO think it's ok to not be at the best spot in your marriage, and date.
AS LONG, as you have that self-awareness, that you can share with those who are involved with you. ( So that you attract the right kind of people, and they don`t feel hood-winked.) Sometimes, dating others, makes you appreciate your spouse and their faults a whole lot more. The grass is not always greener elsewhere.
I think trying poly-style relationships are something of a 'pandoras box' issue. Once you roll it around in your head for awhile,....you will end up trying it.
Like learning anything else, you will fall, flail, flouce around, and make mistakes with it. You will also learn and grow from it. Some people learn and keep going with poly, finding it very rewarding life-long. Yet others learn some lessons, and move away from it.
You just never know.