Can I contest an irrevocable living trust myself?

It has come down to self-representation since I cannot find a lawyer, and I wonder if I can do that. Here is my case that no lawyer will take without min $50K: After my father died, I moved in to take care of my mother, while my sister took care of the money/bills. My mother was stage 4 Parkinsons then, quite bad. After 2 years, she recovered to stage 2; but during that time, my sister seize control of all my mother's assets, except her pension. Here is how: First my father's will was not probated. Then my sister got POA from my mother--my mother signed it. Then my sister wrote a new will for my sister (with the help of a lawyer), and gave it to my mother to sign--she signed it. Then my sister wrote an irrevocable living trust, naming herself and her children as 75% heir of estate and me 25%, and with herslef as judge to give me anything at all. Now, my sister won't give my mother any money from the trust, for her health care. I live with my mother still, caregiver daily.