Heartless girlfriend

I lost my granny last week on Monday. In Africa, at least in my country, wakes usually last 2 to 3 days and we have to sit at a fire to keep warm. On the 1st day I went home at around 19.00 to take a bath. I was so tired i fell asleep and woke up around 22.00 to bath. I went back to the wake after i called a cab at around 23.00. I informed her of this. I spent the remainder of the evening at the fire. By sunrise i was smelling of smoke so i texted my girlfriend who's in America that i was going back home to bath. We were on yahoo chat. She then accused me of being with another woman that i was taking home. I told her i didn't need the stress at that time and it was wrong timing. This was Tuesday morning. She went quiet on me the whole day. I needed her a lot during this time and i felt deserted. My grandmother was buried the next day and she was still quiet. The reason i didn't initiate communication is i'm usually the one to rectify things no matter how wrong she might have been. Anyway she contacted me on Friday and i asked her where she was when i was burying my grandmother, ie why she didn't check up on me. She told me i'm too sensitive and then shocked me by asking me where i was when my grandmother was dying saying if i had seen her more often she might have been alive. She never met my grandmother and vice versa. My gran was a mother and a friend to me. Her words affected me so much i called our relationship off. She never apologised for saying what she said... How do i pick myself up? I had invested so much emotion,time and dedication into this long distance relationship.