By Pritha Sarkar

RIO DE JANEIRO (Reuters) - Bullies are ruining U.S. gymnast Gabby Douglas's Olympic adventure by attacking her appearance, accusing her of being unpatriotic, and by mocking her with a mean-spirited nickname, "Crabby Gabby", on social media, her mother told Reuters.

The 20-year-old athlete has been attacked for a perceived lack of patriotism for not placing her hand over her heart as the U.S. anthem was played during a medal ceremony and for not joining a standing ovation for two team mates.

Her mother, Natalie Hawkins, says Douglas is heart-broken.

"She's had to deal with people criticizing her hair, or people accusing her of bleaching her skin. They said she had breast enhancements, they said she wasn't smiling enough, she's unpatriotic. Then it went to not supporting your team mates. Now you're "Crabby Gabby"," Hawkins said in an interview.

"You name it and she got trampled. What did she ever do to anyone?"

For the second Games running, Douglas has found herself caught in a firestorm despite yet another gold winning performance in Rio.

In 2012 Twitter went into overdrive after Douglas became the first African-American gymnast to win the Olympic all-around title. But rather than lauding her excellence, critics rounded on her for the state of her hair during the final.

Four years on and Douglas has another Olympic gold, from the women's team competition, but the sheen from that victory has also been tarnished after TV cameras showed her standing to attention during the national anthem.

"I don't think respecting your country or your flag boils down to whether you put your hand over your heart or not," Hawkins said.

"It's in your actions towards your country, how well are you abiding by its laws, how well are you helping your fellow citizens?

"We grew up in the military community. My mum spent almost 30 years in the military, my dad's a two-time Vietnam vet. Because of that it was so insulting that they would accuse my daughter of being unpatriotic when we are so tied to the military family.

"When the Star Spangled Banner is played, most military members either salute or stand to attention."

But Tuesday's furor over what the correct protocol is when the American flag is raised was neither the beginning nor the end of Douglas' problems.

She was also criticized for not giving team mates Simone Biles and Aly Raisman a standing ovation when they claimed gold and silver in Thursday's all around final.

With accusations that Douglas was angry and jealous at being denied a place in the final, since rules state only the top two performers from each country can progress to the final, #CrabbyGabby started trending on social media.

"We've been brought to many tears because I don't know what she's done to warrant such an attack. To me it looks like she is being bullied," said Hawkins.

All this unwanted attention on her daughter has been painful for Hawkins to watch. Despite being in Rio to cheer on Douglas, she is unable to give her a comforting hug because of team rules limiting contact to phone calls and texts until they are done competing.

"What I saw in the stands was someone who was hurting and she was also angry," added Hawkins.

"What was going through her head was 'I'm being attacked for everything I do so I might as well not do anything. Because no matter what I do, I am being attacked'."

Did Hawkins think Douglas was targeted because of her race?

"Many people are telling me that all the time. And that's from white people and black people. I don't want to believe (it's a race attack) as I want to have more faith," she said.

"But when I go on Twitter, I can't help but see that all the blacks are saying: 'was it just the white people that are saying this against us?'

"Maybe people are very frustrated. Our country has a lot of unrest and turmoil recently and people are frustrated and maybe they just want to vent and they just see someone innocent ... and bully them."

For now though, Hawkins says she has advised her daughter to stay offline and instead focus on competing in Sunday's asymmetric bars final.

"They keep attacking her about not smiling but they don't know what she is dealing with. If they did, this would not be a conversation. They would (understand). But this is not the time or place to tell that story," said Hawkins, who raised four children as a single mother.

"I want ... people to show me if they have ever seen Gabrielle being disrespectful ... or say something inappropriate. There is nothing because for her being a role model is such a supreme honor.

"Gabrielle's had her heart broken, but she's determined she will go out (on Sunday) and she knows she still has a job to do for Team USA. It's a huge honor for me to be her mother as she's the bravest person I know."

(Reporting by Pritha Sarkar; Editing by Ossian Shine and Mark Bendeich)