I hit 6' and 145 lbs by age 16. I probably gained another 15 or 20 lbs by senior year. I stopped running completely after high school and only occasionally played a sport with friends. Walking onto and across my college campus was my main source of exercise. I was at about about 175 when I graduated from college, got married, and sat in a desk for 8 to 10 hours a day 5 days a week. I got up to about 185 for some time and then by the time I was in my mid to late 40's creep up to 230. My blood pressure was borderline hypertensive and my cholesterol was probably 280.
I finally got scared enough to start walking for exercise and cut my calories to about 1200 a day. Within a week or so a 90 day fitness challenge started at work. I worked up to 2 to 4 miles of waking at 3+ MPH and lost 55 lbs in 90 days. I won contest. I think having a goal and seeing the weekly loss in weight helped. I definitely saw and felt the changes. I started cycling 10 to 25 miles two to three times a week. I think I was back down to 165 or 170 by my next physical. My doctor was happy with the weight loss and said nothing negative about how quickly I lost it--I expected him to have some concern. Someone at work had not seen me for months saw me one day. She had a very concerned look on her face. She quietly ask if I was ill. I think she thought I had a fatal disease because I changed so much.
My daughters eventually talked me into running again. I did not think my bad back could handle it but it did. I slowly got up to 25 to 35 miles per week and stopped counting my calories. I ran a few 5K's and other races over 18 months during which I went from 21+ to mid-19's. Then I got a injury in late 2014. The injury took 3 months to heal. By spring I was probably back up to 190 due to lack of exercise and not limiting calories. I started running in the summer of 2015 and got another injury within a few months so gave up until Thanksgiving. I started walking again with my weight back up to 195. In January I walked and ran a 2 mile route. I moved up to running 2 miles 4 days a week. I slowly increase my mileage but did not lose weight until I changed my mindset and cut my calories two weeks ago. I have lost about 8 lbs in 2 weeks. I plan to get back down to 165 or less. I scheduled my physical for this summer so I have a deadline. No one in my family believes the charts that say a man my height can be healthy as low as 145 so I don't know how low I will go. Another goal is to get back to my training pace I had back in 2014. I am currently about 40 seconds slower per mile than I was in 2014.
Don't let yourself go. Don't let food take over. Don't let a desk career prevent your from getting exercise.