I finished I Want This to Work by Elizabeth Earnshaw a few weeks ago. It's a pretty remarkable book about communication in relationships, and I wanted to take some time to jot down my thoughts and reflections from it.
As far as aspects of my life go, working on relationships is not something I have actively thought about much, or tried to work on and improve. If you consider that relationships make up a big part of most people's lives, this is a bit shocking. If you also consider that the vast majority (I would estimate ~80%) of the experiences and disagreements that you're going to have are applicable to other couples, then it follows that you should have a lot to gain from reading about them.
If you are interested in exploring attachment styles, better communication, and learning the tools to repair after rupture, I can recommend this book. It helped me to heal after a particularly painful break-up, when I came to realize that I didn't really know how to navigate relationships at all.
I've also recommended a few videos (found below) from The School of Life that I found really helpful.
There are 3 types of attachment styles; anxious, avoidant and secure. 50% of the population is secure, and 50% are anxious or avoidant.
Studying your childhood can be extremely valuable. Many of our relational insecurities, fears and unhealthy behaviors are the result of childhood wounds, especially when you notice yourself behaving in a way that doesn't feel in line with your adult self.
Sharing power is even more important in a relationship than active listening, reducing anger, or empathizing.
Both assuming or dismissing how someone feels can be a violation of an emotional boundary. E.g. Saying "Stop worrying, it'll all work out!" can make the person being vulnerable feel like their feelings are being completely dismissed.
In a healthy interdependent (and not co-dependent) relationship, you have to be willing to say the hard things and allow them to feel their feelings in response. Don't try to manage their feelings for them.