The 60-year-old TV presenter had tears in her eyes as she announced on Instagram she had separated from Ben Ofoedu, 50, after 16 years together.
Vorderman, 62, consoled Feltz in an Instagram comment: "He's a....and you have survived far far worse V....you ARE a survivor and I can't wait to be going out with you..as you know."
DJ Sara Cox told her: "We love you Vanessa you’re an amazing woman, an absolute badass & I hope you’re really feeling all this love & support right now."
Singer Shirley Kemp commented: "So sorry Vanessa you will get through this . You have certainly proved that you know how to love and be loved and love will always be with you."
Loose Women's Jane Moore said: "Onwards and upwards."
Myleene Klass reassured her: "You have got this Vanessa and we have got you. You have been so brave and will absolutely rise from this like the Queen you are. You deserve loyalty and love and knowing your worth and not settling for anything less than that takes balls. Proud of you."
And her own daughter Allegra said: "We love and support you always Mummy."
Trisha Goddard wrote: "Check out all the #sistahs and #inspirationalwomen (in the public eye and those who aren’t) who have reached out to you! If that’s not proof that your pain is felt , love and hugs are there for you and your resilience über admired, what is? Sure they’ll be tough times for you once all the adrenalin has gone and reality really hits, but, hey… when you bravely open up in this way, we are all here!"
Feltz had been engaged to the Phats & Small singer since 2006.
She said in a video statement: "My relationship with Ben is over after 16 years and I honestly didn't know what to say to you on Instagram.
"But now it's clear that it's over and I really do feel that once the trust in a relationship is gone then you can't really get it back and that's what I would tell anyone else to do."
She added: "And so I just wanted to say that obviously I feel incredibly sad and I am pretty disappointed and shocked and all those horrible things but also full of resolve. I am not going to let this defeat me.
"I am so glad to be living longer than my mum did, she died at 57 and for the Lord's prayers, I am going to be 61 next month.
"I am very very grateful to be alive and I want to carry on feeling that way and I want to celebrate and find fun and laughter anywhere I can.
"I know it is not going to be easy but I am absolutely determined to do it."
She added the hashtag "broken".
Feltz has previously spoken candidly about how her ex-husband - surgeon Michael Kurer, the father of her two daughters - walked out on her after 17 years of marriage.
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