It was January 2018 when Solomon Thomas’ life changed forever.

Thomas had just completed his rookie season with the 49ers, who selected him No. 3 overall in the 2017 draft. The 6-foot-3, 280-pound defensive end had gotten his feet wet in the league with three sacks, 11 quarterback hits and 10 tackles for losses as a rookie.

On life’s surface, he seemingly had everything going on.

After the season, Thomas was back at his parents’ home in Dallas visiting, and they had plans to meet his sister, Ella, for lunch.

It was a lunch that never took place.

Thomas’ 24-year-old big sister, Ella, a bright light in his life and his best friend, took her life the next morning.

“My mom and I spoke to her the night before,’’ Thomas recalled over the phone on Tuesday. “We were planning to all get lunch tomorrow and that lunch never happened. Ella died by suicide early that morning. We had made plans to go get lunch and talk about her work and what was next for her, told her that we loved her and went to bed thinking there was going to be a tomorrow.’’

Tomorrow took on a much different meaning for Thomas, the Jets’ defensive end.

After a period of time to grieve the loss of Ella, Thomas made it his mission in life to raise mental health awareness and put an end to the stigma around suicide, a taboo subject no one wants to touch.

Thomas used his platform as a professional athlete to launch “The Defensive Line Foundation,’’ which is dedicated to ending the epidemic of youth suicide and make it OK for people to talk about it. Thomas formed the foundation with his parents and his cousin.

It’s because of this kind of fierce dedication off the football field that Thomas was chosen by the Jets as their nominee for the Walter Payton NFL Man of the Year Award — the most prestigious off-the-field honor in the league.

The award recognizes an NFL player for outstanding community service activities off the field, as well as excellence on the field. Each of the league’s 32 nominees were announced Tuesday. The winner will be announced Super Bowl week.

“Oh man, this is such a blessing and a rewarding feeling,’’ Thomas said of being recognized as the Jets nominee. “The honor of being named that by my peers and co-workers means the world. They see the work I put in, they see how much I care about the community, they see how much I want to give back and how much I want to make an impact.

“I believe it’s the highest honor in the NFL outside of any playing accolades. I hold it in high regard.’’

Giving back has been a part of Thomas’ DNA.

“It’s something my parents always instilled in my sister and I,’’ he said. “Every Christmas growing up in Dallas, we’d always wake up at 5 a.m. and feed the homeless at the Austin Street Shelter. It’s what my parents always wanted us to do.’’

Thomas said his sister’s suicide “increased immensely’’ his “passion and drive’’ to want to give back and focus on mental health.

“Ever since Ella died, I understand the huge epidemic we have in the U.S. with mental health and suicide, how big a problem we have,’’ he said. “My family tried our hardest in a lot of areas, and we really do believe we did everything we could for Ella. Learning more about mental health, there are always things where you think, ‘Well, maybe I should have done this or that,’ but that’s also just how it is to deal with suicide, because you have all the ‘ifs ands and buts.’ ’’

That’s a big focus of The Defensive Line — to help people with those ifs ands and buts, and to let people know that “it’s OK not to be OK.’’

Thomas was far from OK after Ella’s suicide, saying, “My deepest depressions occurred after losing Ella, for sure, but in my life I’ve struggled with anxiety.’’

He recalled Robert Saleh, his current head coach with the Jets and then his defensive coordinator with the 49ers, reaching out to him as soon as the news of Ella’s death became public.

“I was depressed and holding it all in and Coach Saleh reached out after Ella died and told me he’s here for me if I need anything, that he’s got my back,’’ Thomas said.

Thomas also credited 49ers head coach Kyle Shanahan and general manager John Lynch for having a profound effect on helping him cope.

“Coach Shanahan made generous donations in honor of Ella to AFSP [American Foundation for Suicide Prevention],’’ Thomas said. “John Lynch did the same thing and he encouraged me to seek the help of therapy, which became a big part of my life and really saving me.’’