My DM isn't a cunt, she is however extremely difficult and probably a bit toxic. She is emotionally stunted and has the maturity of five year old. As a child I had to walk on egg shells because her moods were so unpredictable, they would change like the wind and you never knew what you were going to get. She'd go from being full of the joys of Spring to sulky, slamming doors and giving one world answers in a matter of moments, often for the most ridiculous reasons. She got a stressful job when I was 10 and this got worse, as she would more often than not bring her bad day home with her. We all have bad days but when you are a grown up you have to suck it up and not take it out on others, her lack of maturity makes that impossible sadly.
She was never available for me emotionally. She never listened to me, asked me how my day was or encouraged me to do well at school. Without sounding like a big head, I'm very intelligent and my teachers told her I had the potential to do very well academically but she wasn't interested. I developed mental health problems in my early teens, started school refusing due to anxiety and failed my GCSEs.
All my opinions had to be the same as hers. She would explode in a rage if I didn't tow the line, it could be something a similar simple as not liking the same song that she did. She was controlling, told me what to do and was obsessed with what people though of us. She didn't respect my boundaries, she'd barge in my room without knocking, look through my things etc.
It continues into adulthood. Earlier this year I had a cancer scare, DMs attitude was that it's unlikely to be anything serious and I was being stupid by worrying, she genuinely couldn't understand why I was so terrified and was constantly shot down by her. I honestly had more fucking support from work colleagues I had only know about six months. Yet god forbid she's ever ill she'll expect us to rush to her aid..
She also uses money to manipulate us. Can't give us what we need emotionally, but if I went to her tonight and said I'm broke I need a grand she'd give it me just like that. I'd sooner be on the breadline than feel so emotionally abandoned.