The treatment for bone mets may vary just as chemos may vary. My doc gave me monthly infusions of a drug named Zometa. It helps the bones repair the damage done by the cancer. In addition I was given an ongoing prescription for two pain meds to help manage any flaire up of bone pain. Depending on the amount of damage radation of the bones is also an option.
It is my understanding that women have lived 20+ years with bone mets so there is no reason to think that you will not be around to see your son grow up. I have two children still at home ages 15 and 13 and I plan on being around to see them graduate high school, college, get married, and have children.
Depending on the MRI results, you may want to inquire with your doc about a bone biopsy just for the sound piece of mind it will bring.