DP and I have been together 12 years, 2DC, 6 & 2.5yrs and I think we are broken 
We both have faults, lots of resentment, hostility and anger. It's obvious to me this is not good for the children and I am banging my head on a brick wall that DP can't see we are simply not happy or right together, and there are unresolved issues.
I have been working on and taking responsibility for my behaviour (snappy, irritable and shouty to DP and DC, resentful to DP for not helping out enough) and always try to minimise the impact on the children, if I lapse. DP doesn't have this awareness though and I don't think he can see his role in our troubles. DC deserve so much better than this, it is breaking my heart.
At times I am honestly scared I will be taking all the responsibility/blame if we break up, that DP will get nasty and I will break under the strain. He said a few years ago, during a row, that if we ever broke up he would take the children and say I was "nutty and couldn't cope".
This is deeply offensive and hurtful for many reasons, and on many levels, which he knows.
It terrified me at the time, and it was a good time later (about a year) when I felt strong enough to pull him on it and show him it as abusive. He said he didn't remember and that it was likely just a heat of the moment thing and he obviously (?) didn't mean it. We did go on to have a positive talk about if we did ever split, we would always be able to work things out positively as we usually do, and because the DC will always need both of us as parents to do that (although I realise now these were my words and sentiment to which he agreed). But it has stayed with me, that he could even think and say such a thing.
He can also be disrespectful around my lack of libido, and gets angry and hostile when I turn down his advances (usually late at night when he comes to bed and I am exhausted) and threatens to move permanently to the spare room. He has said we will not get married all the while the lack of sex is an issue, which is fair enough in some ways. I however need to hear and believe this is not an issue if my libido is ever to return (ie take the pressure away) which he struggles to comprehend.
At the same time he also says he will never leave, he is not a deserter and that he cannot entertain the idea of him living in a shared house and only seeing his children at the weekends.
So we are at stale mate.
There is a lot more. A key issue at the moment for me is imbalance in responsibility around the house and parenting, particularly since I want to return to work, developing a new venture which is enormously positive. He thinks I am being selfish and wants me to wait until the children are older. On the other hand I believe it is important for my self-esteem, and will make me a better person, parent and partner.
But, I also know I need his full support if I am to make it work. So I am feeling heartbroken and a failure on both fronts.
This is sounding awful isn't it? I am also in danger of developing a fantasy crush (would never act on) on someone who shares my passion, level and understanding around things that are important to me. I know it's just a symptom of the troubles in our relationship, but it's a crush on someone who could be really helpful to my venture so now I am likely to mess this up too.
I have made the wrong choices, and I am questioning why things have got this far. What a fuck up
Thank you if you got to the end of this and sorry if slow to repond to any replies. I am meant to be writing a funding bid but all this is floating around in my head 
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