You would have had to eat an extra 1000 calories per day to gain 50 pounds in six months! Without knowing your emotional and physical condition, I'd say you were unhappy and filling a void by enjoying food. Step away from the kitchen! Walk, drink water to fill you up and do not eat junk foods! Consume and/or burn 500 calories less per day to lose a pound a week. It's doable in small steps! Good luck and feel better!
It could be stress, a recent tragedy, or you are just getting older. You need to exercise more (30 minutes, 4 times a week), and eat smaller portions of food. I eat about 5 or 6 tiny meals a day, which boosts your metabolism.
Stress produces excess cortisol which retains fat. Like it or not - human bodies are design for physical activity - start walking a mile then two then three a day - and stay away from fried foods, junk food, salty foods, and foods that contain a lot of sugar - like sodas and breads and pasta (which metabolize as sugar spikes - raising insulin to neutralize excess glucose - which raises cortisol to shut off insulin secretion - and stores that extra glucose as glycogen in lipid cells - a left over from evolution). Overall - reduce your caloric intake - but get a copy of the BMI table of common foods - you won't believe how much sugar is in things you had no idea hand any sugar content at all - use this table to know what to avoid - they're online and free. You should also get a physical - make sure you're not heading for Type 2 diabetes. And no booze - almost forgot that one.