Useful guidance on how to help a friend who discloses to you is available on various websites.
The Mothers Union has a handy ‘Dos and Don’ts for for supporting survivors’. https://www.mothersunion.org/2018-16-days-activism-resources
Refuge.org: ‘Help someone you care about’.
For sources of short or long-term emotional support, advocacy, counselling, advice or refuge in the UK, go to the End Violence Against Women website: https://www.endviolenceagainstwomen.org.uk/get-help
Additionally, there is a comprehensive list of organisations with helplines for rape and sexual abuse victims: https://www.itv.com/thismorning/rape-helplines