So this suggestion is assuming that you really are not having fun in combats, and relies on your willingness to completely give up combats in an attempt to make a point. If not, play something reasonable (I might suggest Chameleon if you can get a few levels in it.)
Say that you're playing a psionicist who is completely delusional about his abilities, and write up a normal human psion character. Be IC all the time, and loudly announce your actions, saying, I try to manifest time hop/astral construct etc. Make the DM do the work on what your character can actually do, interspersing things your character can do, things he can't do but the real psion can, and things that psionics can't do.
Tell the GM you're playing this character, and that you're fine with him vetoing the effects of your powers, or changing them based on what he wants to happen. Formalize an agreement that he can decide how your powers actually work, or not, if you want to be obnoxious or spring it on him. My guess is he'll do one of two things.
Pessimistically (and thus probably): ignore you, while you have fun in an immersive roleplaying of a crazy chaotic person, which seems a decent way of salvaging the situation since it sounds like trying to enjoy the tactical battle aspect of it is an exercise in futility.
Optimistically: He realizes that he just wants complete control over what happens, and will make your psion cause random things to happen or adjudicate vague effects to have an ad hoc effect, and you'll be exactly as effective as you'd be otherwise without the frustration of being hit with the fiat bat every time you try something.
If confronted, say you're trying out a new playing style that matches his GMing style. Come up with good reasons. If this fails, have your character take up basketweaving, and read a book or check play by post games online.