In an Instagram posting, the 31-year-old centre back talks of her pain in the wake of a handling error that led to the first goal in Saturday's 2-1 quarter-final loss that ended Canada's tournament. The ball got tangled in her feet and English forward Jodie Taylor pounced on it and scored.
Like many of her teammates, Sesselmann did not speak to reporters after the England game.
"Words cannot describe how utterly heartbroken I am," wrote Sesselmann, who battled back from knee surgery to make the World Cup team. "The tears have not stopped flowing and this one is going to hurt for a really really long time. Yes I slipped, yes they scored and yes you can blame me all you want ... If that's what makes you feel better fine.
"No one knows how hard I worked to get back from injury to be a part of this special team and make a difference. I know my worth and I know all the great things I've done to help this team get here."
Sesselmann then took aim at those who had pointed the finger at her.
"For all you classless people with your negative comments and threats you know absolutely nothing. You can sit there and choose to focus on every negative and pick apart our team BUT you have NO IDEA how much passion, heart and hard work this team puts in. No matter what any of you say I am so damn proud to wear this jersey and so damn proud of what we have accomplished and how hard we fought.
"Yes we aren't perfect and yes we ALL made mistakes, every great athlete makes mistakes ... YOU even make mistakes. ... It's part of life ... but it's how you respond that matters, and we never stopped fighting. And I can promise you all this ... WE WILL be back and WE WILL be better."
Sesselmann thanked her supporters, friends, family and teammates.
"This truly will be a journey I will never forget. I love you all and can't wait for what's to come. The future is extremely bright."
Canadian coach John Herdman, who spoke to the defender on Sunday, said Sesselmann had no need to defend her actions.
"The fans, the majority, are with Lauren. And you felt that straight after the game," Herdman told The Canadian Press on Monday.
The English forward was 40 yards from goal when the mistake happened, rode two tackles, saw a Canadian defender slip, and then scored from the edge of the penalty box, Herdman added.
"Yes, mistakes happen and she (Sesselmann) made one. But she wasn't the only one. And to be honest the people who are really chipping away at Lauren, she doesn't even need to give them any attention."
Herdman said Sesselmann did 90 per cent of things well and 10 per cent not well. "And that's not bad for a player."
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