I'm no pro at this, but I asked one of my favorite nurserymen what to do to kill a non-bearing filbert that was growing up right through one of my nicest big rhodies. He told me to cut the filbert off and leave a stump about 6 inches tall. The next step was to use a throw-away foam paintbrush to paint the stump all over with straight, undiluted brush killer. My friend told me to paint it, wait about 10 min and paint it again, until I had applied the brush killer 6 times. Then he said to cover it with black plastic, then set a box or flowerpot upside down over the plastic wrapped stump and put a brick or something on top to weight it down. Covering the stump is critical my friend told me, because if any light gets to it, it will just sprout up again.
It worked! I checked it within a couple of months and the stump was already rotting away. By painting the brush killer on, it doesn't get on the soil. Brush killer isn't good stuff, but with the 2 plants I was trying to kill, I was desperate for something that would work.
I used the same technique to get rid of a tree my neighbor had planted on our property line many years before. He had been trying to cut it down for about 6 or 8 years, but it kept coming back. The darned thing was sending up shoots all over my yard, and the roots had even invaded and blocked my sewer system. The same treatment my friend told me to use on the non-bearing filbert tree worked on that other tree, too.
This, of course, is only if you want to kill the wisteria and maybe start over with a new one, or try a different type of plant. If you want advice on how to get the wisteria back under control, I have no clue what to tell you. Every person I know who has had wisteria has had the exact same experience as you have had.