Glen Campbell is nominated for an Academy Award in Sunday night's (Feb. 22) ceremony, but if he wins, it will be a bittersweet victory.

Campbell is nominated for Best Original Song in the 87th annual Academy Awards for "I'm Not Gonna Miss You," the final song of his career. The track appears on the soundtrack to the documentary film Glen Campbell: I'll Be Me, for which cameras followed the entertainer on his farewell tour as he struggled with the increasing impact of the disease.

The song came about through something Campbell said to his co-writer, Julian Raymond.

“He had a hard day of people asking him about Alzheimer’s and how he felt about it,” Raymond tells the Wall Street Journal. “He didn’t talk too much about it, but came up to me and said, ‘I don’t know what everybody’s worried about. It’s not like I’m going to miss anyone, anyway.’”

"I'm Not Gonna Miss You" is a powerful track that looks back on Campbell's life, while acknowledging everything his disease is slowly taking from him.

The Journal reports that the 78-year-old country icon's struggle with Alzheimer's has progressed to the point that even if he wins, he will not be able to recognize that fact. Raymond says Campbell no longer has any idea that he was once a top-selling star, and he doesn't recognize Raymond when he visits. Campbell can no longer communicate other than through short phrases.

Campbell's wife, Kim, says despite his struggles, he is content and cheerful. He can still play guitar a little bit, and finds time to pray. She and his children are planning to fly to Los Angeles to attend the Oscars in his place, where they will see Tim McGraw pay tribute to Campbell with a special performance of "I'm Not Gonna Miss You."

The 2015 Oscars are set to air live from the Dolby Theatre in Hollywood on Feb. 22 beginning at 7PM ET on ABC.

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