Waht is your biggest obstruction in loosing weight?

I have a desk job as well. It was easier to lose weight when I had a job that was on my feet all day. If you think about it, people who are running around all day on their feet like in retail and such, are burning so many calories that they don't even have to workout after work. I like to focus on "metabolism" enhancing workouts rather than long, intense workouts that burn a ton of calories. I feel like if I can get my metabolism going, it'll be beneficial all day.

Also, a big obstacle for me is that everyone around me is not trying to lose weight. I do not have a single friend, family member, or coworker trying to lose weight! EVERYONE in my life is constantly ordering pizza and takeout and asking me to go to olive garden and eat those delicious breadsticks with them....having to constantly say no when they're like "oh, one bite wont kill you". But they don't understand. One bite WILL kill me. Because it'll turn into the entire basket of breadsticks, a bowl of chicken alfredo, and tiramisu.