Kate 2.0 vs. Jon Gosselin: "He Needs to Man-Up And Tell the Truth"

Reality lothario's former galpal dishes on their relationship and calls him out as a two-timing liar

Hell hath no fury like a woman scorned...by Jon Gosselin.

Hours after Kate "1.0" Gosselin dished on the Today show, Kate "2.0" Major came into our studios and gave an exclusive interview to E! News calling out her former flame as a "liar" and "two-timer."

"We had plans to travel together, to live together, and to be together," Major says of her whirlwind romance with the reality dad. "He made his decision in the Hamptons. He wanted to be with me."

Just last weeek, Gosselin reportedly said his relationship with Major was strictly platonic.

But, according to Major, 26, Gosselin told her he was going to break up with girlfriend Hailey Glassman, 22, in order to be with Major, and, as a result, Major resigned from her job
as a Star Magazine reporter to avoid a "conflict of interest."

"He told me he was going to Massachusetts to break up with her," says Major. "I know the truth. He knows the truth. Unfortunately she did not."

Still, Gosselin and Glassman are claiming they never broke up, Major says this is a lie.
"He tried to two-time both of us," says Major. "He wasn't honest with Hailey he needs to man up and tell the truth. I'm not going to be the other woman."
Major also claims she has proof that she and Gosselin were "romantically involved."
"I was not the only one who was around when we were romantically involved," says Major. "We were holed up together. It's not like we were just sitting there doing an interview."

Major says Jon was even the one who asked her to quit her job.

"I was with the person I was reporting on...it was a huge conflict of interest," says Major. "He's the one who actually told me to quit my job."

Major also tells E! News:

On the fallout:
"It's been a nightmare. I did not want to have to do this...I have to speak. I did not want to have to sell him out but when he makes me look like a liar, a fool, and an idiot. I have to speak out."

On his getting back with Hailey:
"In no way did he tell me he was going to go parade with his ex-girlfriend."

On moving on:
"This whole experience has taught me so much. When I had Jon's support it was hard, now that I don't it’s even harder."

The entire interview airs Monday night at 7 p.m. ET/PT in a special hour-long edition of E! News.