Published Wednesday, 07 May 2014
Price and Hayler married in August last year. (© Getty)
Price - also known as Jordan - made the announcement during a series of posts on her Twitter page on Wednesday.
She claims Hayler had been having a "full blown sexual affair" with her best friend for seven months.
The news comes just days after Price confirmed reports she was six months pregnant with her fifth child - her second with Hayler.
The couple welcomed baby boy Jett last year.
Price told her followers: "Kieran is a disgusting human being doing this after I've just had a baby and still doing it till I caught them.
"No human being deserves this especially being 6 months pregnant. Worse pain in the world."
Later on Wednesday, Price posted a statement on her official website saying she made "no apologies" for her series of tweets as they "were a sign of my heart breaking".
She added: "I am appalled that someone I loved, trusted and believed in has behaved in this way.
"If he had so little respect for our relationship I would have hoped he would have thought about our child or the one that we have on the way. That he did not means he will no longer be part of my life.
"I will do all I can to ensure he maintains a relationship with his children should he want that.
"I am so grateful for the love of my children and family at this time."
Price is also mum to Junior, 8, and Princess, 6, from her marriage to Peter Andre and 12-year-old Harvey from a previous relationship with footballer Dwight Yorke.
She married builder and part-time stripper Hayler in the Bahamas in January last year.
Price was previously married to Andre and cage fighter Alex Reid.
© UTV News