"HAPPY MOLLYS BIRTHDAY EVERYONE!!!" Bell wrote on her account. "@mmcnearney is one of the kindest, most authentic, cleverest gals I have ever come across. Her intelligence is only outshined by her wit. The world is better with her in it. I LOVE the fact that she exists. This is a very special day."
Aniston split from Theroux in February after less than three years of marriage.
People reported Aniston is leaning on friends, including former "Friends" co-star Courteney Cox, in the wake of her separation.
"Spending time at Courteney's always makes her happy," a source said.
"She has a huge group of girlfriends who make sure she isn't alone," the insider added. "Jen truly has the best friends. They are real friends that she has had for many years. They alway support each other."
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