Advice please!!

Christina • 🇫🇷❤️👧🏻🤰🏻 Ma vie est magnifique.
Hi,
I am 25 year old single mom, I have a 6 year old and my fiancé and I are trying to find our own place. We both live with our parents and we want to get on with our lives. I am currently on my way to my bachelors degree (2.5 years left). Our income together is not much, about $3500/month. We were approved for a house (rent) for $1350 a month (water and sewage included). We were chosen out of a lot of people and we feel honored. When I told my mom, she told me I could not do it and I would not be able to afford it. I need to get out and move on with my life. Being at my parents house is not a bad thing at all I love it here but I feel like I can't be a mother and wife here. My mother will not let my fiancé move in either. I just feel very stuck and I don't know what to do. I get no assistance or child support (my fiancé is not my child's biological father). I almost feel pathetic writing this but I need different views. Thank you so much.