Veterans can receive VA disability benefits for the rest of their life as long as their conditions do not improve. If the veteran passes away from one of those service-connected conditions, their spouse will be eligible for benefits. The VA may order a reexamination of your disabilities and they can reduce your rating. Assuming your service-connected conditions have not improved, you will continue to get VA disability benefits. Veterans can receive Individual Unemployability benefits as long as they do not return to work full time and their conditions do not improve. One way to protect yourself from a rating reduction is to obtain a permanent rating from the VA.
Learn more about permanent VA disability ratings here: