Single Mom Advice

Hi guys. I recently decided to separate from my child's father. I decided the relationship was unhealthy and I would not set that example for my child. 
My son is almost 4 months old. And while I know this is the best decision, I'm terrified my son will suffer. 
Do any single moms have any advice for me? I'd be the first in my family to become a single mother, so family isn't the best support right now.