Life is (and should be) about personal growth. Each person should be free to discover who they can be and grow and develop as a consequence of that. A relationship, in my opinion, should nurture that, rather than restrict it. I think that this is a quite common problem, because of fear - fear that the person may grow to the point where the relationship can no longer survive.
That fear is real - but it should be a reason to stop growing, and live in a cage for the rest of your life.
So what has happened is that you have grown to the point where the relationship dynamic with your husband is no longer giving you want you want out of the relationship. You have a choice - live in the cage, negotiate with your husband to change the relationship dynamic to give you what you want, or end the relationship. The second one is probably the first thing to try. If that doesn't work, then maybe counseling would be good for you, although I am thinking that he may have a problem with that.
It is very tough when folks grow like this - this "till death us do part" garbage that people have this fantasy about. I am always very cautious in the commitments I make in my relationships - nothing is a promise "forever" - if it's *is* forever then that is fantastic.
Please check out The Birdcage - an open, friendly Polyamory forum for all parts of New York State
"Listen, or your tongue will make you deaf." - Native American Proverb