Ok, so how do you go about separating your finances so that you don't need to rely on him so much?
Does he do childcare for you? Can you see about swaping childcare with another mama, so it doesn't cost too much?
In what way does his lack of responsibility affect your life? If you want, we can help you brainstorm ways to separate yourself from him as much as possible and only communicate if it pertains to visitation.
I remember what it's like to NEED my partner's help and to find that no matter how much I begged and screamed, he wouldn't ever give it to me. His concern was HIM and HIM ALONE. The children were there to make him feel good about himself, but only when he needed them. Every other time, they got in his way and gave him an excuse to whine (and drink). The way I got out of it was to stop depending on him for things; I put my daughter in full-time childcare because he couldn't be trusted to care for her during the period where I went back to work and he found himself without a job.