The general rule, for your spouse to receive Chap 35 benefits, is that she has 10yrs to use it. So, she had until 2013 to use her Chap 35 benefits. I believe that once you "die" they give her another 10yrs of Chap 35 benefits, as part of her spouse/DIC benefits. If there was a period during that first 10yrs where she was physically unable to attend classes, they may extend the deadline, if requested. It's not the VA's fault she didn't use the benefit.
As to the VA treating her, it's up to each VAMC, whether they want to allow her to be treated there. She should still be able to use her ChampVA, for treatment, outside the VA.
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