It depends on your age and and your metabolism. Perhaps you are eating more fast food as a result of work and your increased level of income??? Have you ever seen the movie or read the book Fast Food Nation, or seen the movie Supersize Me? And we are just coming off of the holidays here, when weight gain is at its worst.
As a senior in high school I weighed 170 lbs. By the time I was just 19 and in college though, I weighed 190 lbs, and after working in a factory job and eating a lot of fast food everyday for lunch at work I had gained another 20 pounds to 210 lbs, by the age of 21. Then I stayed at that weight until my early 30s when I worked for a truckline where I ran team to California from Denver twice per week, and my partner and I stopped at the casinos in Nevada 4 times per week for the prime rib. In just a year on this job I gained another 25 lbs to 235 lbs, a weight that I held at until I was age 40.
At age 40 my metabolism slowed way down, and no one thought to warn me of the consequences of this and my eating habits. In just 6 months after I turned 40, which also coincided with my 2nd trip to drug rehab, I gained 40 lbs to 275 lbs. Then every Nov/Dec after that I gained 10-15 lbs, though for several years I was able to lose the extra weight through the following year. Then at age 44, I tried to quit smoking the first time, and was off of cigarettes for 7 months. In just that period, which started in November of 2001, I gained another 50 lbs, to 325 lbs. Every holiday since then I have gained another 10 or 15 lbs, and have had trouble loosing the extra weight gain. I lost 50 lbs on the Atkins Diet once only to gain it all back.
And today, not two weeks after the holidays, my weight stands at 350 lbs, up 15 lbs from earlier last Fall. I'm 6'5" too, but I would really like to get back down to 275 or less if I could. I have cut way down on my eating but that has not seemed to help. So my recommendation is that you nip this thing in the bud now instead of waiting until you are in your mid-40 or early 50s and you weigh 250 or 275 lbs or more and can't seem to lose the extra holiday weight like me. You may also need to look into some kind of regular exercise regimen too.
I've been on anti-depressants and I haven't gained any weight as a result, though in my case, anti-depressants always seemed to be a bit on the speedy side. It may be that you are eating more because you feel better about yourself because of increased serotonin levels but that wasn't my personal experience. For high-end medical knowledge with the ability to question their staff by email, try:
www.mayoclinic.com, where they have all kinds of medical info available for free to the general public.
Hope that you can find a way to lose the weight and keep the weight off, though I have heard of a study that says that men with steady girlfriends and married men weigh on average 20-25 lbs more than single men do. You have said that you have a regular girlfriend so I wonder if that could be part of it?
Hope that this help,
Mark