Is it nnormal for my 14 yr old daughter to get real bad pimples between her breasts that leave disgusting scars? if so what should i do?

See doctor: May be boils or a form of cystic acne. She may need an antibiotic or other treatment to avoid scarring.

Yes possible: Don't pop the pimple. Some people tend to make keloid after a cut or wound. So, you don't want to pop any pimple etc. You need to consult skin doctor if the acne is severe. Keep your personal hygiene well-that would help.