That's exactly the problem with mixing your own stuff. Since it's your material, you can easily lose perspective on the mix, and because you want to make sure it's just perfect, you end up in a loop, second guessing your choices and losing direction.
What always works for me is taking a week off (don't touch the project, don't listen to any of the mixes, don't even think about it), then sit down, listen the material through, make notes of stuff that are obviously wrong to your ears, correct them and then
let it go. Convince yourself it's done, and no matter how many times you go back to the beginning this is how good as it's gonna get.
I know letting go of the project is tough as hell, that's where deadlines are helpful