Unlike fellow Hugh Hefner ex-girlfriend Holly Madison, Kendra Wilkinson never saw marrying the Playboy empresario as part of her future.

Now that he's engaged to Crystal Harris, "he's where he wants to be in life, and you know, I'm happy for him," Wilkinson said on 'The Tonight Show' (weeknights, 11:35PM ET on NBC).

Her only concern was that she hadn't been invited to the wedding. So she alerted the media universe, and received an email from Hef shortly thereafter.

It read, "We haven't sent any 'Save the Dates' but if you can't make the planned wedding on June 18, we'll just change the date. Do you think I'd consider getting married without you being there?!"

Whether to offer selfless well-wishes or engage in self torture, Holly Madison decides to head to the Playboy mansion and scope out ex-boyfriend Hugh Hefner and his 24-year-old fiancée Crystal Harris.

"I don't want it to be awkward," Hefner tells her on 'Holly's World' (Sunday, 10:30PM ET, on E!). Oh, but it is. Holly admits, "It's definitely difficult to talk about being engaged with Hef, because he knows how much I wanted to get married and have kids when we were together."

She tells him, "I always feel very protective of you ... If [Crystal] ever messes up, I'll kick her ass." Things get even more uncomfortable when Crystal joins them.

Everyone has an opinion on Hugh Hefner's engagement to 24-year-old Crystal Harris. But what does Holly Madison think? She was Hef's girlfriend (well, one of them) for seven years.

In the season-two premiere of 'Holly's World' (Sun., 10:30PM ET on E!), a friend breaks the news (that she received over Twitter). "I feel like they just started dating," says her gal pal.

Holly used to think she'd get engaged to the Playboy founder. "I thought we were headed towards being exclusive -- marriage and family," Holly explains in voiceover during a photo montage of her with Hef. She ended the relationship when it was clear the 84-year-old wouldn't settle down with her. "I had a lot of different emotions and thoughts on [the news]. This was kind of a shock."