I'm really sorry to hear this about your relationship with your mum. Something that I always try to remind myself when I feel that someone doesn't care about me is that this is an assumption that I am telling myself is correct, even when it very well might not be. My advice to you is to talk to your mum about it in a calm and collected manner. Ask her to spend the night watching a movie or ask if there is something she would enjoy doing together. Once you have started on a positive note like this, she won't feel so attacked if you let her know your thoughts. It could even be something as simple as telling her that you're feeling alone and like no one really cares for you at the moment. I don't think it is likely that she wants you to feel this way, some people just express that they care in different ways. Another thing you could do is talk to your father and ask him if he has any experiences of when he knew that your mother cared about him. He might be able to tell you stories and you might realise that she shows her love differently.
If you don't feel confident doing this straight away then maybe just try to have a few nights together where you spend some quality time doing something you both like and tell her that you have enjoyed those nights together and ask if she does too, this is a great way to let someone know you care.