Forgiveness: It is so hard

Isn't it amazing how one event in your day can ruin your whole attitude and mood and determine if it is horrible or good. Today has been a horrible day, although it didn't start that way. It started out perfect the sun was up early so I got a workout in early and got to listen to the birds chirping and breath in the fresh air. I was able to be so productive and everything was falling into place. Class even got out early which never happens, so how could this day go wrong. One phone call is all it took. What is amazing to me is that right before this "phone call" I was actually talking to a girl sitting next to me about a bible study group she wanted me to join with her and we discussed Christ and the impact he has had on our lives. The demons were obviously not happy because not two minutes after I walked away did my phone ring. It was my mother. Like a lot of girls I have had problems with my mom and we have not always gotten along. Recently though she has turned into a beast and has been so hateful, judgmental, and out of control. Well to make a long story short she cussed me out, accused me of being a liar, and being the most ungrateful person she has ever known. I was so upset at first but now I am really angry about it. Yes, I was sort of wrong in the situation and I apologized and tried to me christian like, but then she kept on going... Why is it that this had to happen today? Normally when a situation like this happens I would call family members and complain and rant about it. Like I have said before though I am a changed woman. After hanging up the phone with tears in my eyes I bowed my head and prayed for my forgiveness and prayed for her. I am still angry, but I know I will be able to forgive and forget now that Christ is my go to person. I hope that things will get better soon, but they rarely do with her, and I am even considering not going home for Easter and going to a service here by myself instead of with my family. I know it sounds wrong, but I am so hurt by her. How can such a christian woman do this to her daughter? Even through difficult days I find strength through Jesus and in one of my favorite parables: The parable of the unmerciful Servant:

"Then Peter came to Jesus and asked, "Lord, how many times shall I forgive my brother when he sins against me? Up to seven times?"Jesus answered, "I tell you, not seven times, but seventy-seven times."Therefore, the kingdom of heaven is like a king who wanted to settle accounts with his servants." Matthew 18:21-23