This forums is about discussing polyamory. The focus here is very often on relationships with other people, especially more than one other person.
I'm not sure if it's neglected, or if it's a given that's never mentioned, but the first and primary relationship must always be with yourself. No relationship works well without you knowing yourself. And given the added complexity of open relationships, jumping into that without an understanding of yourself will lead to disaster quite a bit faster than maintaining a mono relationship without that understanding, but I'm pretty sure the result will be the same either way. Relationships can't build and snowball without two people bringing things to the table.
And I'm not accusing you of bringing nothing to the table, quite the opposite. But if you don't know what it is you're bringing, it's impossible to build from it.
It sounds like you've got issues surrounding sex as well as physical barriers to a strong libido. I'd suggest working on those first, to be true to yourself.
I'd also suggest talking to your husband honestly. Write it down first if you need to. I've confused sex and closeness before and he might be as well. Perhaps he might find some peace and even more patience by understanding flat out that your lack of desire for sex isn't a rejection of him. Hopefully, this will open the door for you to express and explore what it is you're feeling, which might help you deal with the aforementioned issues.
Connection is the path to passion. Passion is not the path to connection.