No, it's not called venting, you are sharing an experience that has deeply upset you.

This is what I would do.

Focus on the "task" at hand.

Somehow or other you are going to have to let your inner self shine - you are much better than this person who treats you "like a p.o.s." You're worth more, you can do more, and you can achieve more.

Don't let this pathetic co-worker win. They're not worth it.

So look at the "what" needs to be done and go out and get it (in the workplace) and as hard as it is; put this nasty co-worker and thoughts of what they have done to the side as you look forward and move towards the place that you deserve to be.

You deserve to be happy and you deserve to achieve.