You show her that even if she doesn't love YOU, you love her no matter what, I'm sure she cares, she may just have a hard time showing it or may regret things she's said. Try having more bonding time with her and talking more about things she's interested in.
Stay positive. What ever you do DONT do anything that could damage your future. Examples:neglecting school work, smoking, drinking, drugs, fornication, etc. Maybe pick up a hobby that will get you out of the house and away from her often, like sports!
Well try bonding and talking and try doing things your mom loves to do or be more helpful or volunteering to do stuff for her maybe she does and you may not see or understand the ways she shows her love and how she cares more than likely your mother loves you shes in your life as a mother figure and wants to be and supporting you she may not show it but may show it in another way by being tough on you cause she wants the best for you and for you to follow your dreams and stand alone without depending on the love of others there maybe many reason but telling her how you feel is a good start in mending a relationship and getting to know how your mom does and act by bonding and spending more time with herr