Was on vacation & didn't come here the last 10 days or so. I'm sorry you are still struggling w/ this so much & about having to see your H holding hands w/ OW.
It is a very confusing time in our lives when everything we believed about the person we trusted so deeply gets turned upside down. It makes it hard to get oriented on more than just the relationship issues. Have you seen an IT? Have you considered going to a psychiatrist to discuss medication? As this confusion seems to be really impacting your ability to get oriented enough to effectively work on your sitch, they may be able to help give you some temporary relief to make things a bit more manageable until you are able to work through your issues and get to that point on your own?
I like Matt's analogy on goal setting, but I'd add that you also want to understand what your pattern has been in responding to your H so far. Since it hasn't been working, you need to think about what you've been doing so that you can try something new to zero in on the honey. This gets to the other question posed to you, at least in small part: What is wrong w/ your M?
We all develop strategies to protect ourselves, move away from pain, pursue pleasure, many of which we developed by the time we were 5 or 6. They brought short term relief, comfort, and soothing at that time, and we modified them according to the range of options that opened up to us as adults, but they are still the same basic patterns learned then. To use myself as an example, I would often use put downs couched in jokes as a tool to ward off and make myself feel better about myself. The jokes and put downs got more sophisticated and subtle as I got older, but the pattern was there from an early age.
In a sense, when push comes to shove, we are all still taking the advice of our five year-old selves as to how to deal with the situation. These often cause us problems in our Rs, and your H's complaints likely touch on these, even if there is an MLC going on. Being in a very painful state that we are at this horrible time in our lives gives us the motivation to take a look at these and work on changing them. When we are comfortable, we lack the motivation to change. When we are suffering, we have the motivation to do the hard work necessary. With the wisdom & insights of spending a lot of time and doing a lot of hard work reflecting on ourselves and our patterns, we can use that opportunity to make our lives and the lives of those close to us a lot happier. It may not fix your M, but you will come out a lot better, able to have healthier Rs in the future, and be happier.
So, besides focusing on GAL goals, now is a good time to focus on PatientMan's "scary" question. You'll get help and support along the way to make it easier. Again, consider IC if you aren't already doing this (we can't sit there for 50 minutes face to face, reading your body language, and most of us lack the training and years of experience a good IC has), & my suggestion of consulting a psychiatrist for some medical relief if the struggling seems to be really harming your ability to function in your life or deal with your sitch (the latter seems to be the case from your posts).
Hang in there. It will get easier and if you stick with it, you will at least gain some insights and new habits and activities that will bring some joy to compensate for the pain.
Me: 50 W:43 S6, S3 M: 12 yrs. T: 17 M is bad & Not happy Bomb Mar '14 S 5 Feb '15 D Bomb 13 Apr '15 (but "no hurry") DB Coach May '15 Wants proceed on D Aug '15 Starting 1-on-1 negotiations Sept '15