What to do with the soul survivor of a pair of bonded parakeets?

This happened to me a few years ago. I had a bonded pair of budgies (parakeets), but the female died of egg binding. The male was very depressed after that. We tried talking to him, feeding him his favorite foods, playing with him and included him in family events (eating dinner, playing cards). Less then a month later, he died. We believe it was from depression, but he was also old. I think the depression weakened him and he died of a heat attack on July 4th. We had other budgies, but I just think he was so sad about his mate. Try keeping your budgie happy by doing the things we tried with our budgie. I would also advise getting some another budgie to keep her company.