Is a Doula worth the money?

Shannon • 36 year old mom of 1 and pregnant with #2 (yay)!!!
I cannot have an epidural and suffered a terribly hard labor with son. My birthing staff at Kaiser was unattentive and didn't help at all through the process. I am 18 weeks with my second child and starting to research ways to make this time a round more enjoyable positive experience. I've had several friends say YES a doula is invaluable but several have said NO don't waste the money their experience was not pleasant. Any moms out there with advise?