Oxford University student Ione Wells, 20, was attacked as she walked home near Camden earlier this month
She said the reaction to her letter, first published in student paper The Cherwell, had "transformed" an "incredibly hurtful" experience.
Ms Wells said she hoped the letter would bring hope to other victims.
A 17-year-old has admitted sexual assault and will appear at Highbury Corner Magistrates' Court on 6 May for sentencing.
Ms Wells, who waived her right to anonymity to speak about the late night attack, said the experience would not change her.
She wrote: "My community will not feel we are unsafe walking back home after dark. We will get on the last Tube home, and we will walk up our streets alone, because we will not ingrain or submit to the idea that we are putting ourselves in danger in doing soâ€¦ Your community - even if you can't see it around you every day. It is there. It is everywhere."
She was widely praised for her bravery, and efforts to promote online hashtag campaign #NotGuilty, which argues sexual attacks are never the victim's fault.
"I'm very pleased that something incredibly upsetting and incredibly hurtful has been able to transform into something which I feel really, really positive about," she said.
"I had hoped that writing this letter would not just be for me.....it is for other victims and their communities to feel somebody is standing up for them."
In response to public feedback, Ms Wells tweeted: "Wow - what a wonderful community. YOU have all proved my points about community in your support. Thank you! Let's do this! #notguilty"
A woman who wrote an open letter to the man who sexually assaulted her has said the public response has made her feel "positive" about the ordeal.