Dollarama

I've been working at Dollarama since August 2017 and at the beginning it was great. Then about 7 month in the manager Vicki was unpredictable and always on our backs, lying and leaving the store early and changing the time on the computer before the week paid period. Then she left and they gave us Frederick who did the same and would also make us key holder and then remove it once he found the male staff he wanted.. made us lie about the shrink and say it was always the delivery trucks and the stolen stuff was also the deliveries, if we didn't do it, he would threatened us to fire and not have EI.
Now recently, the pass year, it's been drama were assistant manager( Nathalie Pelletier) and manager lie about things and write everyone up for nothing .. either we didn't empty the skids on time to being late, forgetting cash of closing time to closing the back door appropriate.
I've been in the hospital in and out because of stress and drama because I can't handle being at work over worked and minimized and thrown under the bus that I didn't do my task, which I did and they say to DM I didnt.. they say the same about my colleagues and also written up for missing work with doctor's note, also giving me over hours which we established from the beginning that I can only do 15hours to mac 20 but given 25 hours and all mix. The assistant manager keeps on stating lies to my manager about me, saying she said, he said.. very rude by text or brought in office. Talks to me about my colleagues how they are not good at work, their lazy and should be fired. Boss talks about the same to me and then turns her back and says the same about me to my assistant manager. Also insults my son of 12 years old because he has ADHD and cannot babysit himself and I often call in sick or need to attend his school, so she said, I should leave him at home and teach him to babysit himself to my assistant manager .

It's all of that type of drama, constant write ups to push me to quit, threatened me, cut my hours to 4 hours a week to have me quit and then management talk trash about my colleagues to minimize and threatened people to quit so EI is not optional.

I am very drained and don't know what to do.
I lost weight, sleep and very tired and depress because I enjoy my job but my environment is poisson.

Please help me find a solution