I second that. Taking the steps to get information together so you can see exactly where you stand.
I think that's an issue for a lot of women who have stayed home many years. My Mother left my Father when she was a little older than you are now. She had also been a stay at home parent. She went and got a job at a leather goods store. She loved it, she was very good at it and that experience brought her new friendships and she got meet a lot of nice people every day who appreciated her. All in all a very positive experience.
She rented an apartment, my younger sibling lived with her there for a while.
Between child support and perhaps some alimony (you will find out more about this from the lawyer) and a full or part time job, you may well be able to handle this.
Another alternative may be to go ahead with a separation or divorce but live in the same house. Is it possible to divide the house living areas at all? He lives in the basement for instance and you upstairs and you share common areas, which you obviously will not be hanging around in together. This might be an in-between solution while you get organized.
In the meantime, small steps, like you are taking. Remember to take good care of yourself too.