Nelson and her partner, Jim Morrison, were climbing the eighth highest peak in the world when she went missing just below the summit on Monday, according to her sponsor, North Face.
"There are no words to describe the love for this woman, my life partner, my lover, my best friend, and my mountain partner," Morrison wrote on his verified Instagram account on Wednesday. "She has been the beacon of light in my life day in and day out."
Morrison said the two had "reached the true summit of Manaslu in tough conditions" at around 10:42 a.m. on Monday and "quickly transitioned from climbing to skiing in cold and wind with a plan to ski around the corner and regroup with our Sherpa team" before a small avalanche followed.
"She was swept off her feet and carried down a narrow snow slope down the south side (opposite from climbing route) of the mountain over 5000’," Morrison wrote. "I did everything I could to locate her but was unable to go down the face as I hoped to find her alive and live my life with her."
Nelson's body was retrieved by a high line drop from a helicopter and taken to Kathmandu on Wednesday, officials told ABC News.
Morrison said he was part of search efforts for Nelson prior to her body being discovered, which included landing at 22,000 feet, along with other mountaineers.