Travis Hunter can only blame himself for his relationship being a hot topic -- at least that's what Nate Burleson is saying ... 'cause he tells TMZ Sports the Heisman winner could've avoided all the criticism if he just kept quiet about his private life.
The Colorado superstar and his fiancée, Leanna, have been forced to defend themselves from the haters recently ... following months of piling on from folks on the internet.
Burleson weighed in on the drama out in NYC this week .