Help and advice on getting flowers for a girl?

Long story short: I was pushy and hurt my girlfriend (not physically). We had a long distance relationship, I haven't seen her since August. She broke up with me on Wednesday last week. I want to do something to apologize, she'll be home this Wednesday night. I was thinking of getting her roses but I didn't know how many or what kind. A couple of my friends think that a single rose would be better. Should I get a bouquet or would one be better? They think it's symbolic.