Communication and listening has always been the bread and butter of a relationship. I have been with the same man for about 10 years now and this has become a staple in our relationship. It sounds like you already know one of the biggest flaws you have in communication which is great that you can confront that characteristic about yourself, so practice working on that. Focus on listening to the subject instead of formulating a response and missing the entire issue in the first place.

Around our five year mark, we established an open-door policy so that if either of us ever had a problem, we could immediately voice our concern (even if it seemed to come out of nowhere) so that these assumptions and complaints don't fester and become worse off. I know how this might sound, as a lot of people I've presented this to in my personal life seem to think that negotiation is impossible in the battle of the sexes. But it takes realizing no one wins in an argument with your spouse to see that you should both working together and not trying to hurt each other.

What can I do to help fix this all and make us happy again?

A relationship takes two people to make it work. When you start thinking long-term it no longer becomes about "I" but about "us". I can't tell the specifics of your relationship from a paragraph alone, but I believe that opening up channels of communication, especially to topics which may make the conversation seem tense or uncomfortable, form strong trust over time when everyone realizes they have an equal voice in the relationship.

I'm not going to lie and say that you will be eternally happy with no snags in the future. But this is why it's important to practice effective communication for when these road blocks in your relationship do form so they can be dealt with in a healthy way that won't damage the relationship or create resentment.

If you're looking for suggestions in reading material, try reading The 7 Habits of Highly Effective People by Stephen Covey. Stephen Covey has some good sections that illustrate how good and bad communication work in your personal life and how you can practice to change your attitude via language. He also talks largely about listening when it comes to effective communication!