She doesn't deserve forgiveness

I hate my mother, I always will. It all started when I was about 13, she had been a stay at home mum up to this point, so blamed her children for this and always resented us for not having a career (it’s not my fault she decided to procreate 5 times and drop out of school at 16). One day she was called to jury duty, and happened to love being in the environment, so long story short she joined the police and that when it began with her staying out late, not coming home and getting regularly drunk with her new ‘friends’. Dad and my brothers and sisters decided this was just a phase, let her relive her twenties, but it just got worse and worse. By this time my brother and sister’s were at university, so I had to look after myself and my little brother, my dad was working all the time to pay for my mother’s over expenditures and we were getting into more and more dept, but I think he also just wanted to escape from being around my mother if she was ever home. I loved horses, and I had one called Sula, she was amazing, but one day I came home from school to find out my mother had sold her without even telling me, I couldn’t even say goodbye. We could no longer afford her... 3 months later my dad found a bill for £1000 worth of motor bike lessons, and then she went and bought a £4000 bike. It wasn’t long after that that they finally got a divorce, eventually she agreed to move out, but only after my dad had to give her a huge pay out. The only contact we ever get from her is through her lawyer about money complaints, and that it’s not fair that he can stop paying her is she gets re-married. WHAT?          Why should I care? Why in Hell should I conform to societies rules and forgive my mother after everything she’s done to me? All I get from people outside my family (who also  hate her) is ‘but she’s still your mum after all, she’ll always be there’. NO SHE WON’T. She decided one day that she no longer wanted to be a mother to her 5 children, and buggered off with her punter of a boyfriend, taking all of my dad’s money with her! After the divorce went through, it was agreed they would have joint ‘custody’, yet I’ve not stayed with her once, hell I don’t know where she lives. The last contact I had with that woman was 6 months ago through a mass text she sent to me and my siblings saying she hated us and never wanted to see us again.   I’m 18 now, and my family and I are finally recovering from everything she’s put us through, but it’s been a long hurtful process, but I don’t care what anyone says, she made me live out my teenage years  cutting, being a closet bulimic and in and fear that she would finally drive my dad crazy and he would leave, but he never did, he unlike her, has always been there, always cared for me. She will never be involved in anything I do in life, and I don’t care if people call me unforgiving for hoping she burns in hell, because it’s where she belongs.