I'm no expert on relationships except when it comes to my own. There are many relationship theories out there and I have come up with my own relationship laws. Here are just a few:
1) I am responsible for the quality of my relationships.
2) I only maintain relationships that are positive, productive, and profitable.
3) I teach people how to treat me.
I'm okay ending relationships. I now live by the mantra of "I love you, but I love myself more." I am okay being alone. In fact, I prefer solitude to sociality. It is not selfish to want alone time nor is it selfish to make and keep appointments with yourself.
It is your responsibility to speak up for what you want and need in a relationship. Assertiveness is essential if you want to avoid miscommunications and misunderstandings. I was programmed to suck it up and serve in relationships and I am still unable to express what I want, initially. I'm working on being straightforward and expressing my needs and desires as soon as I'm aware of them. I no longer consider it admirable to be a suffering saint nor a noble martyr. I enjoy being around happy, fulfilled people. Their cup runneth o'er and blesseth all those standing near.