Hi
Speaking from experience, I would say your husbands lack of support could be down to his own insecurity. You will be changing, physically and mentally as the pounds drop off. You will feel and look totally different, become more confident, sexy and obviously you will dress differently.
All this will worry him, other men may start to take notice, you will maybe want to do things you would never have contemplated doing before - losing alot of weight is a life changing experience. He just needs reasurance that although you are doing something for yourself, the benefits will be for him too - he should be proud that you have found the stength to do something that will make you feel so much better about yourself and how you feel.