Depressed

I started feeling depress because i’m a single mother and the father of my daughter doesn’t wanna do shit for her & me,he always disrespects me,i loved him so much it’s hard for me to let go and be happy. I feel like a failed, being a single mother a 20 years old…. I stated being depressed and started smoking again,i was sober since i found out that i was pregnant with my daughter….But yesterday night and this morning i smoke a joint for the first time. I’m little stressed because i breastfeeding & i don’t know if it’s dangerous for my baby I feel like i’m loosing it and i can’t be certain that i’ll not smoke ever again…