guilt

I was having a decent week even though my moods are often flip floppy because of the stress of living with him, they flip flop to keep up with him.
Now today i come to work and talk to my mom, i love my mom to death but yesterday my H stopped by and talked to her and layed on the sweetness and his charm and now she feels bad for him that i want to leave. She knows every thing that has happened and knows why i want to but she also feels like he is her son because he lived with us from 17 on, so she does remember the good in him.
So that makes me remember the good in him and then i feel guilty that he has no idea that i want to leave.  I know my mom didn't mean to lay this on me and she knows what is best for me and her grandson but yet she can't help but feel bad for him, even though he has demonstrated his cruelty on nearly every member of my family.
She knows that i have gave him every opportunity to change but he won't he always goes back to how he really is. I know she knows hes just acting most of the time but still has the same issues i do when he is good, he's good, sweet and charming, makes you almost forget how cruel he can be. 
I just wish i could get past this all, start a new chapter in my life, so tired of feeling guilty for wanting to be happy, instead of faking it constantly....