Selena Gomez on the set of 'Spring Breakers'

Justin Bieber's girlfriend Selena Gomez is unhappy with her pal Ashley Benson and it is all over another friend getting dumped.

Selena and Justin haven't split this week, (at least so far) however, when Ashley dumped another good friend of Selena's, Gomez was said to have felt ''used'' and ''punched in the face'' by Benson.

The 'Spring Breakers' co-stars are said to have fallen out after Ashley dumped her boyfriend Ryan Good - a close friend of Selena's man, Justin Bieber - to date James Franco.

A source told RadarOnline.com: ''Selena feels used and kind of punched in the face, seeing as though she got Ashley the role and Ashley just used the opportunity to break her friend's heart.

''After Emma Roberts turned down the role because she didn't want to gain weight for it, Ashley practically begged Selena to get her in front of producers for the part.

''She did, because she thought they were all friends, but it was clear early on that Ashley had something going on with James.''

The friend added Ryan started to feel something was wrong when Ashley, 22, started to withdraw, and suddenly started showing great interest in James, 34.

The source added: ''Once the shoot wrapped, Ashley told Ryan they needed to 'slow down' and then booked a flight to New York City to go see James' art gallery showing.

''Selena is p***ed off that she went out of her way to vouch for Ashley, only to have her dump Ryan. [Ashley may have] got the role and got the man, but she lost a good friend.''

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