Mark Alan Shideler


Mark was born in Grand Junction, CO as the only child of John A. and Mary Ellen Shideler on March 31st 1951. The family moved to Arvada, CO where Mark graduated from Arvada West High School in 1969. He attended Mesa Junior College in Grand Junction, CO in 1969. By 1970, there was an avid Star Trek group who met daily at the Student Union. That’s where he met his soon-to-be best friend, Nancy Whiting, of Gunnison, CO.

Mark and Nancy married in August 1974. The couple lived in the Denver area until 1978 when they moved toSheridan, WY. Mark went to work at GAB (General Adjustment Bureau) as an insurance adjuster. In 1981, their first son, Eric Alan, was born followed by John Vernon in 1984. In 1983, Mark went to work for National Farmers Union as an agent for all forms of insurance. He eventually joined Weaver InsuranceAgency where he retired due to health issues in 2020.

In 1986, they moved to the Big Horn area with an unobstructed view of the mountains and a beautiful home that was remodeled over the years. They enjoyed attending their son’s activities including soccer, football, track and other events at Big Horn School. Through the years, Mark and Nancy enjoyed trips to the Santa Fe opera, golf, a trip to Hawaii with Nell (mother-in-law), and constantly reading books.

The most recent move was back to Sheridan in 2022. Over the past year, Mark’s health began to decline. He passed away suddenly and unexpectedly in the hospital with his best friend and wife Nancy at his side. He is survived by his wife, Nancy, sons John and Eric, and his wife Sadie, step granddaughter Savannah, and granddaughter Jocelyn Jean. Also surviving him are his mother-in-law, Nell Whiting, and sister-in-law, LuAnn Whiting and Randy Graupner. Niece Amy Funderberg, her husband Ken, and their daughters Courtney and Alayna. Niece Sara Graupner and her partner, Brian Johnson.

He was a loving husband, father, grandpa, and friend who will be missed by many. Until then, Live Long and Prosper.

There will be a gathering of friends at Champions Funeral Home Chapel Saturday, September 30th, from 2-4pm. A private family gathering will be held at a later date.

Online condolences may be written at

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September 30, 2023
Start Time:
Gathering of friends from 2-4 pm. A private family gathering will be held at a later date.
Champion Funeral Home


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