Back on track to a healthy body

42 year old divorced, mother of 4,(21,17,15,&12) looking to get back on track and improve my overall health, physical strength, while providing a healthy outlet for the stressors of life.
I like to run (5k-1/2 Marathon), like Insanity, LOVE boot camp, would like to start a weight lifting program.
I need help figuring the best place to start without overdoing it. While having accountabilty, allowing for motivation from a group of like minded people.
Any individuals on the same boat...let's do this.