Make amends or a not-so-sweet goodbye?

My sister is about ten years older than I am and, because of this, we’ve never had much of a relationship. Now, I’m nearly sixteen and, because of events in the past year (before then, too, but especially in this past year), the little relationship we had is no longer existent. Long story short, because of a December 2010 fallout, she more or less hates me. While I was at school, she used to spam my phone with texts about how worthless I am, how I’m a disgrace to the family name and how my family/friends would be better off without a screw-up like myself. Her frustrations would sometimes be so overwhelming that she would attack me physically, too (one time, over a clump of dryer lint in a trash bag-less trashcan, she dug her nails into my arms). As of now, I have no desire for any sort of relationship with her, but my family insists that I apologize to her to put an end to the tension. I’ve gone over the pros and cons in my head and, really, the only pro I can see for myself is that I’ll be able to do more “teenager-like” things (e.g. get my permit, stay after school for clubs, etc.) because she’s easy transportation (my mom’s a single mother with four kids). That’s not a good reason to make amends, though; it’s selfish. So, my question is, do I make amends to make my family happy or do I say goodbye to the transportation means of my teenage life (all I do is study now...)?