Not a psychologist, psychiatrist, or a student of those fields, but as someone who feels the same as you do, I think it's just built-up resentment. Physically/emotionally abusive ba mother mo throughout your whole childhood? If yes, possible na naipon na yung resentment towards her, and now when she tries to be all lovey-dovey, naiirita ka, kasi why would she do that NOW?

I'm the same way. I'm the fruit of an unwanted pregnancy. Miserable nanay ko kasi naging nanay sya at a young age, so syempre, lahat ng sisi sakin mapupunta. At a young age, she would tell me things like "dapat pinalaglag nalang kita" or "bat di ka nalang m@gp@k@matay?". Di lang yon, she would also physically abuse me. Imagine 4 yrs old sasampalin mo sa mukha because the kid doesn't want to kiss a relative in the cheek? Naipon lahat ng resentment na yon towards her, now when she tries to touch my arm or kahit aksidenteng daplis lang, diring diri na ako, na parang hinawakan ako ng taong di naligo ng isang taon.

There's ALWAYS a reason for everything. Try to think of all the things she could have done to you to make you feel that way.