I want to make this question more clear/less personal, so here goes.
I am working with a senior co-worker who is not acting professionally towards me and generally speaking, has not ever acted professionally towards me. I'm wondering how to act professional towards someone like this as an entry level employee. He has said (to me and my managers) that I am lazy and worthless even though there is proof to the contrary. But he doesn't treat me like I have valid or reasonable questions and is flippant and rude.
I do not have any options to work with someone else and he won't be fired for treating me this way (because there would be no one left to do the work that he and I are supposed to be doing). He could be reprimanded, but probably not fired.
What behavior is "acting professional" towards someone who has seniority over you and knows that they're pretty much safe from losing their job, but is acting rudely towards you?
Personal, background information
Today I had a meeting with my old manager, the temporary manager (head of our department) and a co-worker. We were talking about the need to give me sufficient training. I am entry-level and my co-worker is senior level.
My co-worker, the person who was supposed to be training me, called me lazy and essentially worthless. He accused me of not doing any work. All of this is wrong and there is proof of this... so, my manager and the temporary manager seem to be with me as far as this issue is concerned. I'm worried about moving ahead past this.
I do not want to work with this guy, but at the moment my temporary manger has no alternative to the situation (as my co-worker is the only person available to train me). Not only would this be a blow to my self-esteem, but this guy is petty, rude, and holds grudges. I don’t know how to approach him and I don’t want to work with him if I have the choice. Sometimes, it seems, I will have to work with him.