Do you have motherhood PTSD? Regrets?

I'm going through a very hurtful situation concerning my 25 yr old son. He's disrespectful to me and blames me for his problems. Everyone that knows me has always saw me as a good mom. To make matters worst, he just had a baby and I haven't seen the child due to drama with the child's mom. It makes me angry inside when I think of all the sacrifaces I've made in my life. Drugs (weed,pills) are also involved so I assume that's part of the reason for their behavior.