Bethenny Frankel's current boyfriend Dennis Shields and ex-husband Jason Hoppy and are in a serious feud.

Hoppy allegedly sent The Real Housewives of New York star an overwhelming number of "disgusting and harassing emails," according to TMZ, prompting Shields -- who was cc'ed on the emails -- to fight back.

Shields reportedly claims that Hoppy called Frankel "ugly, old and irrelevant," in the emails.

Shields has reportedly threatened to sue Hoppy if he does not stop, but Hoppy insists he is forced to interact with Frankel's new boyfriend since the man is now in his six-year-old daughter Bryn's life.

Hoppy sent a letter to Shields' lawyer in response to the potential lawsuit, saying, "As a concerned father, I often have to contact others when I cannot reach my daughter through her mother."

Hoppy didn't necessarily deny the offensive content in his emails, TMZ reported, but reiterated how he has "no choice but to have some type of relationship" with Shields because of his child.

Frankel confirmed she was dating Shields, a New York banker, in June and that a mutual friend introduced them about 27 years ago.

"He's legally married and separated, which is exactly what I am so we're a perfect match," Frankel joked with People this past summer.

"I am in a really happy place right now. I haven't been this happy in a really long time, and I'm continuing with my policy of not involving [others] in my relationships, because it certainly has served me wrong in the past."

Frankel filed for divorce from Hoppy, a pharmaceutical sales executive, in January 2013 after nearly three years of marriage and the court battle turned out to be excruciating. Frankel once went as far as to say the proceedings were "emotional torture." Their divorce was finalized in July.

The eighth season of The Real Housewives of New York wrapped in mid-September.