There are national veteran cemetery all over the country. Many states have their own vet cemeteries. Depending on eligibility the VA can supply caskets, headstone, etc for free even if he is not laid to rest in a national cemetery.
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If you aren't married to him you probably need a will from him stating what he wants.
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PDD with Psychotic Features, GAD, Cluster C personality traits - No meds, except a weekly ketamine infusion