From my perspective you have made some terrible choices in the past. Staying in a marriage where sex was a strong need of yours and you husband denied that need was indeed a terrible choice. I do not blame you for wanting to end this marriage.
But look, do the ethincal thing. Divorce him and then find a man to play with. Do not use your husband for financial support while you ho around. Take the financial hit and reclaim your life. You've lived a marriage of convenience for far to long. End it if your husband refuses to meet your need for sex. Sex is a part of marriage and he shouldn't have ever married you if he couldn't be bothered to provide you what you need.
