Do you think I should tell my mom to fuck off?
Why would you tell your mom to fuck off?
Because she never helped me when I was a kid and now I have to work hard to cope with my life.
Using profanity is not going to be helpful to the situation and just makes you come across in a negative light. Maybe you should try talking calmly about how her behavior affected you and work toward improving the relationship.
She won't respond to that.
Even so, cursing at your mom isn't going to make her understand how what she did affected you so negatively. Instead, maybe you could write down your feelings and let her read it.