What would you do / say ?

So I just had my daughter a few weeks ago..her dad and I are together but obviously when you first have a baby sometimes you have issues.. HIS father tries to butt in our relationship so I looked at my SO's phone earlier and I saw his dad was telling him to leave me...just to worry about taking care of the baby, That I am lazy (Just had a baby 5 weeks ago and I am exclusively breastfeeding) & that he doesnt need to take care of me because all I am doing is LAYING around... Mind you, we live at the apartment underneath my parents home, so I have help, just not all the time. I got frustrated because I am not gonna just throw my baby in day care , just to work and spend all the money from working on day care and not see her at all. DAY care costs a fortune! It makes NO sense when I can just stay home with her, take my online classes and work from home. 
But apparently I am lazy... No I am simply taking care of my daughter..and he knew I wanted to do this for at least 1 year.
Anyways. At this point I do not like his father one bit and need advice as to what you ladies would say or do ? I told my SO how I felt and he doesn't really comprehend. I really want to tell his father off.  He told my SO that I used him for a black child.... (SO is part black, I am mixed with italian, Spanish and Irish) ... That is what ticked me off. I would never USE someone for a child.
Did anyone deal with the same type of thing? Thanks.

Glow Resources

Let’s Glow

Glow is here for you on your path to pregnancy

Glow helps you navigate your fertility journey with smart tools, personalized insights, and guidance from medical experts who understand what matters most.

25+ million

Users

4.8 stars

200k+ app ratings

20+

Medical advisors