You don't have to divorce in order to change things in your life.
I lived apart from my ex for quite some time and when things didn't change I knew it was time to divorce. I didn't make the decision without counsel from others, and I knew at that time it was the right thing to do. I have no regrets.
It is a process, and you can take it as slowly or as quickly as you are ready to do so. I had to go - I was sick myself over it.