There are different kinds of relationships. Some are involuntary, meaning we are more-or-less stuck with certain people, and just have to make the most of our relationships with them. Examples include family members, neighbors, coworkers, fellow students, etc.
Other relationships are purely voluntary, as with friends and romantic partners. Because we hand pick these relationships, we hold great expectations for them. These connections can be the greatest blessings of our lives, or can go terribly wrong. What started out as mutually satisfying can morph into a draining or unloving situation. Sometimes it happens so gradually or insidiously, that we don't even recognize that our "good" friendship has gone bad.
Doreen Virtue's book, Assertiveness for Earth Angels, outlines ways in which nice, well-meaning people sometimes fall into relationship traps such as rescuing behavior, accepting blame, being disrespected or allowing ourselves to be taken advantage of or abused, and how they can recognize and learn to deal assertively with toxic dynamics and people.
The following is a list of relationship "red flags" from Doreen's book. (When we identify that something feels off, we can take steps to correct it, and ideally this is done through establishing personal boundaries and expressing ourselves assertively.)
4. Clingy Neediness
11. Accusatory Tendencies
13. Controlling Behavior
14. Perpetual Clowning
16. Substance Abuse
17. Lack of Boundaries
23. Drama Queen or King
24. Taking Advantage (of generosity)
25. Barbed Tongue
26. Nonstop Talking
Nobody's perfect, and you may see shades of yourself on the above list, but if one or more of the above dynamics is pervasive in your relationship, you may want to take action to change it. If you need help or guidance with this, there are many helpful books and online articles available to help you.
Good luck, and have a beautiful week.