I think an important consideration is what effect (long-term effect) will it have on you emotionally and psychologically if you become responsible for your brothers going to jail, but then, on the other hand, they should be taken off the street, they should not have the ability to rape children. You have a responsibility to put them in jail for that reason. You're parents are being and have been very irresponsible in letting this happen and are trying to dump this on you. They hope that you will remain silent and not expose their cowardice in their handling of this since years earlier (personally, I would put your parents in jail also). The reason you don't hate your brothers is because you have love in your heart (love doesn't make sense, it's not supposed to, it goes beyond rationality, that's how you know it's true love). You didn't do ANYTHING to deserve being mistreated, no one should be mistreated by family, no one in life ever deserves to be raped.
I grew up in a dysfunctional family (no sexual abuse, but abuse is abuse). I suffered 51 years of suicidal Depression (I recovered about a year ago). Your virginity is still intact (virginity is not really a physical thing, it is more a state of heart and soul, in other words, you didn't lose any part of you). I think that for the safety of other children you should go to the police. You will get more than just dirty looks, but the ones giving you the dirty looks are who belong in jail. Seek the support of relatives (now, it's very important, you'll need it). You also need to make sure that it doesn't happen again to you, it never should have, so going to the police is an obligation to yourself also, not just an obligation to society. You did NOTHING to deserve this, nobody can do anything to deserve this, it happened because that's just the way the world is sometimes,...people mistreat people, some people choose to live according to their conscience and some ignore (cowards) theirs, but it's NOT your fault.