David Spade, Nicollette Sheridan

Is this love or desperation?

Three months after calling it quits with crooning fiancé Michael Bolton, Nicollette Sheridan is turning her attention to David Spade.

The two got hot and heavy over the weekend at L.A.'s Luau, where Sheridan celebrated her 45th birthday by "full-on making out" with Spade, People reports.

Though Sheridan and Spade arrived separately and started dinner in different booths, they couldn't resist each other for long, eventually holing themselves up in a single booth. "They cuddled and kissed," an eyewitness says.

Later in the evening, Spade "winked at her and stood by her side" while Sheridan — who was joined by Desperate Housewives castmates Neal McDouough, Kyle MacLachlan, Felicity Huffman, and Huffman's husband William H. Macy blew out the candles on her specialty cake, which said "Happy Birthday Princessa."

But don't send out a new couple alert yet — despite their PDA, a source says the two are not dating.

Spade's past flings have included Lara Flynn Boyle, Julie Bowen, Heather Locklear and Playmate Jillian Grace, with whom he has a baby daughter.

Do you think this was a random hookup or something more? And why does Spade have such a way with the ladies?