a 42 year old trying to get back on track

Hello to all of you ladies.
I did P90X as well as TurboJam before and i noticed that I have always felt my best when i excercised. It helped get rid of the stress. I have been very far now from any kind of activity due to a stressful job the last 3 years, demanding life and home with children and an aging parent in need of help. I also have suffered a concussion mid-February and hit the back of my head on my ceramic floor while riding my daughter's hoverboard at home. This is almost my heaviest weight now but I see an example in front of me who is suffering in as she ages mainly due to her weight. I don't want to be like that. I want to be strong till it's time to hand in the keys - death. Trying to start by eating right but life happens.