My mother bullies me by telling me the bad things about me and never says anything positive I'm 13 and how do I deal with this?

Sadly, not everyone is strong and coping and positive all the time. You could try waiting for some time when she is not angry and ask her if you are helpful around the house. Ask her if she ever sees you doing good things. It may be that in a quiet moment she will say some good things about you. Tell her you'd like to help some more. Ask her for advice about things. She may be worried you are growing up too fast, but if you ask her for help and advice she may be able to see the good things in you.

Meanwhile you have to be strong yourself. Can you get friendly feelings from any other relations or friends, father, brothers, sisters, uncles, aunts. Is there a school counsellor or teacher you can talk to?

-----------------------------------------------------------------------------------------------------

She may be trying just to help you improve on your weak spots. But you are probably getting the wrong idea of what she's trying to "say". To tell her, you could directly tell her, or if your nervous, write her a letter and leave it someplace only she'll see it (ex: her makeup bag or her drawer.) Also, it's technically not Child abuse as long as she don't physically hurt you. I'm sure she loves you and wants to help you improve.