It's important that you share the struggle you've had coming to terms with your sexuality with him — how the last thing you want to do is hurt him, but that it's something you must discuss and worked through. Your husband may try to become the model husband, believing that if he is everything you want in a spouse, you might just change your mind.
If you are a lesbian and you decide to leave your marriage, there are many, major decisions to be made. Your revelation will likely cause hurt, tears and sadness. The realization that you be changing your family situation forever by talking about your sexual orientation can seem overwhelming. But, just as you reassured your husband that it is not his fault, remember that it is not your fault, either. Many of us got married without realizing we love women. Perhaps you felt like you had no choice but to get married despite your same-sex attraction.
Your stress and anxiety is temporary. While the ramifications of such a huge, personal change can seem daunting, this is the beginning of a period of amazing personal growth. These conversations are not easy, but they are necessary in order for you to move forward with your life and your new, true identity.