Let's hear it for assistants!
All the teaching 'assistants' I have are awesome and we work with each other very differently. If they want to get involved, I embrace it... if they want to sit at the back and mark books or check Facebook, I'm OK with that too. The longer you stay in one job, the easier it gets to be accepted and the antagonisms diminish. The 'secret' for me has been to completely distance myself from co-workers socially and to ONLY interact with them professionally. No chats, no lunches, no social meetings outside my classroom. It's 'work' for them and it's 'work' for me, however you choose to interpret the word.
Mark