But former Leicester Tigers star Ellis, who won 27 caps for England, insists his days in rugby are far from over.
"I have applied to study Sports Science at Loughborough University and hopefully that will help me go into coaching or teaching," said Ellis.
"I want to stay in rugby and that's the route that I want to go down.
"Leicester have been brilliant to me and I have had great support from everyone in the game. When something like this happens, you do learn about people.
"I have had a lot of great conversations, text messages and telephone calls from all around the world.
"I've had a great time in rugby and capped it all off by playing for the Lions. I know there are plenty more people worse off than me."
Meanwhile, the baton of the No9 jersey for both club and country has been passed onto 20-year-old Ben Youngs, and Ellis believes the future is bright for England's up-and-coming half-back.
"Ben is immense and a great player. He shows great maturity for his age but there is more to come," added Ellis, who came on as a replacement during the Lions' third-Test win against the Springboks last summer.
"He's a genuine threat around the park, not just at rucks and mauls. He scored a great try against Australia from the back of a line-out and has all the attributes to have a great career if he stays injury-free."