Are there any charities for abuse victims - both men and women?

Yes, there are many; some in your own community. Call 211. They are the experts in non profits in your area. The need is great; the opportunities are endless.

Catholic Charities operates Abused Women Shelters throughout the USA

Domestic violence shelters and sexual assault centers usually are set up to help both men and women -- the reason they help far, far more women is because far more women are assaulted (and killed) by partners than men, and women are usually much, much more vulnerable (their partners have often forced them to not work, not have friends, etc.). Call your local domestic violence shelter and ask if you can volunteer. You will go through an orientation that will help you understand domestic violence, both in general and in your community in particular.

Parents Anonymous works to prevent child abuse. Use their national web site to find out if they have a chapter in your community.

Also go to VolunteerMatch, if you are in the USA, to see if any organizations focused on abuse of any kind are operating in your area and need volunteers.

You can join http://www.connecttocharity.com/ to do charity for the non-profit charities listed there. You have to search for the charity working for abuse victims.