Out of the greatest sorrows of life comes the deepest appreciation for things. This is what "Grey's Anatomy" actor Patrick Dempsey realized when he lost his mother to cancer.

Amanda Dempsey died in 2014 after 17 years of battling with ovarian cancer. It was a devastating time for Patrick who was close with his mum. It is even harder because Amanda suffered for a long time and there was always uncertainty on whether mum would still be alive the next day.

Furthermore, Amanda had to deal with the recurrence of cancer for a heartbreaking 12 times. She died at the age of 79.

In "Grey's Anatomy," Patrick plays surgeon Derek Shepherd who was married to Meredith Gray (Ellen Pompeo). Patrick's character died in 2015 in a tragic car accident.

Dempsey revealed that he was grateful for being part of the show, but that it had been long enough. He also shared how he had plans of quitting the show earlier.

Could the passing of his mother be one of the reasons why McDreamy left the show?

Only he could say that. But, even before his mother died, Dempsey was already involved in helping other people battling cancer. Through Patrick Dempsey Center for Cancer Hope & Healing in Central Maine Medical Center, he hopes to give support to cancer patients and their families.

A People's Choice award winner, Dempsey shares how grateful he feels for the opportunity to offer free care to cancer patients. The charity he opened up in Lewiston, Maine has been making a big impact in their community.

The 53-year-old actor shares that he fosters inspiration from the people he works with. He specifically talked about people who are keen on improving the lives of others in a completely selfless way.

Dempsey does not ask anything in return for the free cancer care that he offers at the Maine center. He believes that the meaning of life is altruism and the world needs more of these selfless acts.

Recalling his mother's battle with cancer, the actor reveals how devastating it is to have someone in the family diagnosed with cancer. He said that he has never been the same since his mother was diagnosed. He describes the change as profound.

"There is a darker side of life, but then comes the lighter side as well," reveals the actor about what he learned from the experience.

Today, Patrick welcomes an increasing number of sponsors and fundraisers at his center. Indeed, more and more are encouraged towards altruism because of him.

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