I think if you just take you and the kids you will start to feel independent and empowered. I know it feels funny to do family things without him, but it has to start somewhere. You already made the decision to separate from him, now act the part. This does not mean there won't be times for him to participate, but for now flex your independence muscles and I know you will feel stronger (and have less doubts about the divorce).

I hope you and your kids have a wonderful time.