I have a relative who was in an abusive relationship and she called the local Crisis Clinic and received a lot of helpful information regarding her options and the resources that were available to her.  I believe that every geographic area has some sort of local crisis hot line and they generally provide good support.  Trauma and depression is one of the things they are there for.

Your friend is the victim of sexual harassment and abuse by legal definition.  There is little that you, personally, can do to help him - he must take the steps to help himself before this episode becomes a focal point for the rest of his life.  ndvh.org is the site for the National Domestic Violence Hotline - there are lists of resources state by state.  He can also contact his local law enforcement, but I would suggest to him that it would be far more effective to align himself with an advocacy organization, first.  Unfortunately, sexual harassment of men is so under-reported because of the stigma and ridicule that they experience, as victims, by law enforcement and the legal system.  He needs to be prepared for this through counseling.