as hard as it sounds, your first step should be to report it.
regarding a revenge spell, there's several options depending on the level you're hoping to achieve, if you want your 'friend' to be sent down, look into spells to bring you good fortune, make a liar confess, or to help win a court case. if you want some type of karmic retribution [a la an eye for an eye] you might look into the 'you messed with a witch' hex. if you're looking for stronger curses there are more to choose from [though i won't post them in the forums]
at the end of all this, you should try and heal. it's horrible what happened and it wasn't right, but bitterness is a poison that will keep hurting you. it's fine to be angry, it's fine to want revenge, just don't get lost in the fire. take care.