If she is on the end and that is the end she locked, double chain the gate and have next door neighbor park blocking it or making it a 2" squeeze for her to get by.
If you didn't get an attorney - that was the reason you lost.
There is no problem, no matter how vexing, that cannot be solved by the proper and thoughtful use of explosives.
Run for city council the next time your rep is up for re-election. Then get your friends elected in other wards. A situation similar to what you have described is how my family got into politics.
Living in Memphis is the real problem.
If that does not work, see if you can find older surveys from 1960's, or even earlier. What you are looking for is called a right of way or guaranteed egress.
Don't go thinking you have right of adverse possession unless you are also paying property taxes on that land.
The long and short of it is, you all need lawyers, but you can cut down on some of the expense by doing some legwork yourselves. Good luck.