Pain in the DONKEY grass!

I am at my wits end and ready to buy some Glyphosphate for what i am calling Crab Grass. I really don't like to spray but i'm totally lost at what else to do. It sends runners throughout the garden and the blades have come up through 6" of mulch!!! I CAN'T GET RID OF THIS CRAP!!! HELP!!! I roto-till the edges 6" deep every week and by the time the next week comes along the crap has come back. The only natural thing i have found that kills it is straight vinegar and salt but that has spread and killed some of my turf grass. I've even burned it with my torch and it comes back more vigorous than ever!!

Try a cardboard sheetmulch. This is the only way I was able to garden in bermudagrass and nutsedge in Georgia. If you can spare the area from planting, perhaps a section at a time, for a year or two, the control will be better than if you try to plant through it right away as is often recommended. Just lay overlapping pieces of cardboard, the bigger pieces the better (try furniture and mattress store dumpsters!), at least two layers thick. Just cover with a top-mulch to keep it from blowing away until next season before adding compost, etc. on top. If you already have the area planted, lay smaller pieces, and paper of any sort, on top of the grass between the plants, tucking al the grass under as best you can, and once again holding all in place with a loose mulch on top. You will find that even though the grass snakes through eventually it will usually give your plants enough of a jump on it to be productive anyway. With tough players like bermuda you may need to put paper/cardboard down every year. Nothing else I tried worked....not tilling, not chickens or pigs penned on an area for months, not plastic mulch to solar-cook the topsoil....

First off, every piece of running grass root can grow into a new plant, so I suggest you stop rototilling...
Running grasses are really tough customers and virtually impossible to eradicate.
As with Alder, barriers are the most effective way I've found. They need to be thick, overlapping and perimeters must be patrolled for escapees!
I find old carpet is good. It can be cut to fit and I generally run it up the sides of things like fences, bed edges etc a bit, and make sure it's really tightly fitting.
It aint pretty on its own: lay it upside-down and cover with chipped wood mulch.
But many people aren't comfortable using carpet because of the toxic chemicals in it's construction.
Basically all carpet, unless it's really ancient, has plastic strips woven through the base which can get everywhere if it's moved when the pile's broken down.
Offtopic, but worth saying while I'm going on about carpet:...I never use carpet around trees: the strips choke growing trees and it prevents the feeder roots accessing oxygen.

Yeah, carpet is amazing stuff, and I've used it for everything from ponds and cisterns to buildings. By the time I had collected enough of it, I had left bermuda heaven for another site....but I did find it useful to subdue persistent tree-stump sprouts in my new orchard there!