Is Jessica Biel Putting On a Brave Face?

We wonder if Justin Timberlake's ex is trying to act tough in the midst of her split

Jessica Biel was all smiles at Café Entourage on Saturday, just three days after the big break-up with Justin Timberlake. 

Throwing her brother a 20th birthday bash, Jess—who just turned 29 (one year away from the dating age death sentence)—seemed in good spirits at the party. 

But now that Justin has quickly moved on with A-list beauty, Mila Kunis, do you really expect us to believe that Jess' smile isn't all for show?

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Oh no, we will not be fooled in this celeb breakup. 

After all, Justin and Jess have been on the rocks forevs, and we know JB was not the one in this duo to end the relaysh.

Bottomline: Justin is red-hot right now, and Jess? Well, the days have passed since she garnered attention for her hot bod and fuchsia dress at the 2007 Oscars. The gal even told Vogue last month that her relationship with Justin is "the most precious thing I have in my life."

So sad, really, but we highly doubt the gal is doing a-okay. 

We've said it before, and we'll say it again: Hollywood relationships rarely work when a couple is unbalanced on the celeb stardom scale. 

You can't fool us Jess, so time to put on a sexy dress, show off that famous backside and do what Hollywood starlets do best. 

Good, old-fashioned revenge. 

—With Additional Reporting by Alyssa Toomey