De Mars, a former Judo world champ, says she completely understands why Rousey wouldn't want to shake hands with her adversary, because doing so would go against everything she stands for.
Rousey's whole gimmick is that she doesn't want to be "fake nice" in the manner that she feels Tate is, so shaking her hand would be the dishonest thing to do.
"If you lie about someone behind their back, disrespect them and their friends, I completely understand if that person doesn't want to shake hands with you," De Mars said. "Pretending that 'It's all good now' might make the liar feel better but I don't see why you should do it. If that's what you think you should do, then I won't tell you how to run your life, but I personally have seen a lot of organizations that are completely ineffective because everyone tries to get along, and people who are dishonest or incompetent stick around because no one wants to get in their face and tell them to get the hell out."
De Mars says Rousey is a much better role model than most other athletes in their mid-20s. Rousey may have shown a bit of a lack of sportsmanship towards Tate, but it's not like she broke any laws.
"Ronda is 26 years old and in a very public arena. If you think of all of the things you see from entertainers and professional athletes - DUI, steroid use, wild parties, drug rehab, multiple extramarital affairs and on and on. Or just think of the average 26-year-old. If you're a parent and the WORST thing anyone can say about your 26-year-old child is that he or she says 'F*ck' and didn't shake someone's hand, you ought to go to mass, light candles, get down on your knees and say a prayer of thanks," De Mars wrote.
Rousey is already set for her next challenge, as she'll battle Sara McMann in the main event of UFC 170.