Should I cancel our wedding after catching fiancé lying?

Me(25F) and my fiancé(31M) were due to get married at the beginning of this October. We have been In a relationship since 2018, have a 2 year old child together, we broke up for a little less than a year after some problems connecting mentally, have gotten back together in the beginning of this year and are currently living in a one bedroom apartment. A few days ago I applied to a two bedroom apartment and put both of our information on the app to send it in. I tour the apartment while he is at work and the landlord loves me so much she says that as soon as the application comes through we can move in. To my surprise I get a call back saying we don’t qualify. She then lets me know that I can qualify on my own, but tells me my fiancé has insanely bad credit, is in financial legal trouble, is thousands and thousands of dollars in debt and his car is out for repo. She told me he hadn’t made any payment in close to a year. He hid all of this from me, he let me take our son out driving in this car, he was buying things he didn’t need and still not able to save much. I was paying the majority of the bills and I make more that $10 an hour less than him. I can’t fathom where his money has been going. My mother says to stay with him and work things out but I don’t think I can start a marriage like that. I’m not sure I can ever trust him again.