Woodenpeg, my love, you're not accountable for their actions. They chose to rape.
One of my friends was raped, stone cold sober, at 6.00pm, coming home from lectures, my two close calls were on occasions when the rape apology industry would say I'd done the responsible and sensible thing in getting a man to walk me home (I was sober on both occasions) - in each case, it was the man in a position of trust, the man I thought I knew, not some stranger leaping out of a dark alley, who tried to coerce me into having sex when I didn't want to.
In our culture, going out for a few drinks is perfectly normal behaviour. Sometimes people have the rotten, bad luck to be raped after this perfectly normal behaviour. They also get raped while engaged in other perfectly normal behaviour - walking home from lectures, going out jogging, getting taxis. And even in cultures which severly or totally curtail women's freedom of movement and action (Saudi Arabia, Afghanistan), women still get raped. Rape happens because some men think they're entitled to have sex without a woman's consent, because they don't think women are human beings (and by thinking this, as far as I'm concerned, the men concerned have opted out of the human race and should be locked up and the key thrown away). You had the misfortune to encounter two men who had this attitude - and it could have happened to you no matter what you were doing.
I hope finding the enormous courage to talk about it here is part of the healing process for you, and you can start to talk about it in real life, and get the reassurance you need to accept that it wasn't your fault.