Jennifer Aniston has finally found bliss in her famous rocky love life with fiance Justin Theroux, and now the actress is dispensing romantic advice to her friends.

The primary pal who Aniston is dishing words of wisdom to is her friend Ashley Cusato, an actress who has begun casually dating Mel Gibson. But Aniston is urging her friend to steer clear of the "Braveheart" actor, who has an unpredictable and sometimes violent past.

Aniston was shocked when she found out that Cusato was spending time with Gibson and has tried to convince her to break it off, according to a new report.

"Jen respects Mel as an actor, but he's not the type of guys she'd want her friends to date - he's a heartbreaker," said a source close to Aniston. "Ashley insisted that he'll be different with her, but Jen didn't buy it."

Aniston, 43, has reportedly reminded her friend of Gibson's history with cheating and the vile and threatening phone messages he has left past girlfriends that ended up leaking online.

"Jen wants to be supportive, but she fears it won't be long before Ashley is crying on her shoulder," the insider added.

Cusato isn't the only woman Aniston has been giving love advice to lately. Other reports have said that singer Katy Perry has been in touch with Aniston about her relationship with John Mayer, the notorious womanizer who Aniston dated for about a year.

"Jennifer gave Katy her number and told her to call any time, but she didn't expect her to take the offer so seriously," a source said. "Now Katy's in contact and asking her for tactics on how to tame him, but John seems to know about it and isn't happy that his ex has become so involved in his relationship. Jennifer's trying to wean Katy off, telling her that she doesn't want John to think she's meddling, but Katy won't be put off."

Perhaps Perry started making the calls after she heard that Aniston felt she should dump Mayer and move on. An insider close to the former "Friends" star said several weeks ago that Aniston was telling pals she wished Perry would learn from the mistakes in the relationship between Aniston and Mayer, according to a report from Perez Hilton.

"Katy should really watch out. Take it from Jen. She's been there and done that," the source said. "And it took her years to recover. Jennifer gave John more than a year to prove himself as marriage material. Katy needs to be warned about John's hypnotic ways before its too late."