What would you have done????

Growing up I always knew that she hated me!  When I wanted love I went to dad or found it else where. 
But, all that was sweep under the rug.

Now that I'm older and now have a child of my own I Never knew she would show all that hatred for me to me in front of my child. 

Guys, please tell me if I'm wrong or give me your suggestions of What you would have done. 

Here goes
So, today my son who is 2 was being very rude he wanted his way and What he did was wrong.  So I slapped him, my mother then took him and started hugging Him and called me a fool.

I was so hurt and sad I didn't say anything to her I just walked out the room and went to chill and get the my mind relaxed.