I really feel for you and empathize with you. My story is pretty similar: I lost a bunch of weight and kept it off for a few years with careful eating and lots of exercise. Then I fell into a depressive slump, stopped exercising, starting drinking, stopped controlling my eating and wound up gaining 70lb in about 2 years. I've been struggling for the last year or two to get motivated to re-start all my weight loss practices. It's hard, hard, hard. This week I felt the 'click' so I'm trying to go with it. For me, this means being really strict about exercise so that it becomes a true habit, and logging all my food and all my alcohol in a quasi-obsessive manner. It's the only way I can really lose weight.
I really, really hope you have your 'click' moment and just start doing what you need to do to take control of your life, your body and your happiness. We know that you CAN do it, you just need to find a way to move your will!
One place to start might be to stop worrying about what other people are thinking about you. It's a deadend trap of a thought process and it is going to make you feel worse, more depressed and helpless, less motivated and etc. You can't control other people's thoughts or feelings and ulitmately, they aren't important. What is important is how you feel and whether you are loving enough towards yourself to do what you need to do to feel better about yourself. You need a mantra: "screw 'em, they're not important" would be a possibility.