AS Steve Jobs said (paraphrasing) "Life is short. Don't spend it living someone else's life. Follow your own heart."
My misery and misguided sense of duty lasted 10 years. He almost killed me before I got away from him and the whole mess. If you have kids chances are they will understand. Don't ever badmouth their dad, he'll do it himself and you will shine even brighter.
I've been married 39.4 years to a wonderful man (but whose counting) and still have spasm of insecurity, but also days and days of thanking God and my dh for freedom. Whether you remarry or not (and its not something you can plan... I don't think) quilt, have girl friends, enjoy your family, put a pad in your car and travel, whatever turns you on. The fact that you have gotten out of a bad marriage says tons for you!
Fly girl!