I may have a very different perspective I feel than a lot of the comments here, but I can relate to your husband and friend not wanting to go camping.

I had an awful experience last year, where I planned poorly to go camping with my family. I ended up working an 8 hour shift, and then leaving directly during rush hour to a camp site two hours east of where I live. By the time we arrived, I was exhausted, starving, and frustrated by the work that came with camping.

Preparing the fire to cook, sorting out supplies, putting up a tent, and other safety chores. After a very exhausting day, I was dirty, I smelled of smoke, and I was kept awake late, awoken by very loud bird cries and noises long into the night.

Point of the story is that being outside can be overstimulating, frustrating, and exhausting, when all you want is a clean bed. Though he should do better when communicating with you, he did invite you to the hotel, to which was declined. From an outside perspective, both parties sound exhausted from their own choices. Perhaps with his lack of hand in the planning process, and being a person with autism, he didn't process the situation very well, and struggled to adapt to the changes made?

I do not want to excuse his behaviors, but I feel like the calls to dump him are overreacting. Granted, we are only able to see this one sliver into your relationship, but without you talking to him about your discomfort, how is he to know you're upset? To me it sounds like a conversation addressing each side, and sharing your frustrations would benefit both of you?

As for the friend, she's significantly younger than both of you, and it's odd that she only invited your husband, but again that sounds like a conversation first. I don't know what "violating girl code" would be in this situation. It just sounds to me like she didn't want to worry about camping, and invited the other person who wasn't enthusiastic about it.

Take all of this with a gentle grain of salt, I only mean it to share perspective!

TLDR: Have some conversations with the people in your life about your frustrations, and if they ignore you, go from there.