Goodness me - I haven't read a SINGLE reply but I have to jump straight in and say that you, down to every last T - was me, about 2 years ago. Honestly, I'm almost jumping on the spot it's so eerie. So from someone whose situation was exactly (down to the smallest detail) that of yours in the recent past, this is my story:
I left the DH. While there was a lot good, I mean really good, about our relationship, it was not enough. I wasn't supported enough, I was under appreciated. There were a couple of extraneous circumstances that eventually ended the relationship (slight emotional affairs on both parts), but essentially, I hadn't quite realised how bad my marriage really was until after it had ended. I'm still having little revelations here and there: it's only just fully dawned on me at how much I had on my plate, and really how unsupported I really was - the 'yeah I'm tired too' really resonates.
So 2 years down the line, having gone through the boggy hell that is the process of separation - on the whole I am so much happier. We have 50/50 residence, it's not / not been a walk in the park, but my soul no longer feel destroyed. If anything, I'm busier - but it's a much more wholesome feeling of business. My mental health is nowhere near shipshape, but I am happier in myself overall.
I'm not saying leave. While the similarities are surprising, yours is a different life, a different marriage. But I do wish I had really allowed myself to look brutally at my relationship and made a decision based on that, rather than the sticky end we met. I think we both could have healed quicker as individuals sooner. Try and get some time to yourself. Selfishly and unashamedly demand it from your DH. And try really clear your head for how you would like to see your life pan out from here on in - you can't keep on like you are. Counselling I think is a very good plan. Whatever you decide, you have to make changes, and now is the time.