News flash---all husbands get on their wives nerves, but you know what? We get on their nerves, too. Yep, believe it or not, you are most likely just as annoying to him as he is to you! It's kind of just part of the package deal. Some people are more laid-back, some more uptight so they allow it to "get to" them more.
As for the showering every night before bed, that falls into the category of "adult decisions" meaning once you're an adult, it is 100% your decision ONLY. Sure, you can bug him about it, you can not like it, you can let it drive you absolutely insane if you so choose, but he still gets the final say. Personally, I hate showering at night because then I go to sleep with wet hair. I prefer if my husband showers at night only because it frees up our only bathroom for me in the morning, but it's up to him whether or not he does.
Lighten up, sweetie. This stuff you're stressing over, totally not worth it! ;)