That is EXACTLY how I felt with my ex fiancé!!! I felt used because she was so insecure, I felt drained after conversations practically begging for the time we used to share together. I know she works, but it seems it just consumed her, that and a bad past experience with a man. But it became so toxic with no empathy from her at all, I finally gave up and walked away. I hope she would get help, but as I got out of my sadness for walking away, I felt better because I finally could do the things she would get upset at me for doing. I hope she finds the help she really needs, I just couldn't do it anymore, I hope it didn't make me a coward for walking away, I tried so hard, so many times, tried to tell her it was wrong just to ignore my feelings or needs and walk away.