I've yo-yo dieted since I was a teenager, but in my adult years (20's until 40's), I've lost and regained 50 lbs. twice, so I know where you're coming from.
Here are some suggestions/comments:
1) Re-evaluate your goals. I've finally realized now that I am willing to accept a weight that's a bit higher that I might have liked in the past because that higher weight allows me to be more relaxed with my eating. For instance, in the past, I my goal weight was always 130, which is certainly a reasonable weight for me. However, now 145 seems fine to me. I know that I could get to 130, but in doing so, I'd have to give up much of the food I enjoy regularly, and I'm not willing to do that. The same with exercise. I do 20 minutes of cardio a day, maximum (I do some push-ups, sit-ups, and lunges, too). I could do an hour on the treadmill each day, but I know that I don't want to do that for the rest of my life. (Also, when I know that all I have to do is 20 minutes, it keeps me more consistent).
2) Don't let negative self-talk get the best of you. If you're like me, you've lost some self-trust, i.e., you do not trust yourself to keep the weight off because you've regained it once before. Sometimes that lack of self-trust can translate into negative self talk. Examples: "What's the use? I love food too much. I'll never be able to be a healthy weight!" Counter that negative self-talk with positive comments. I know that sounds like psycho-babble, but it works.
3) Be clear about your goals to your wife. I, too, live with a spouse who can eat whatever he wants without gaining. Also, my spouse tends to oversimplify the ease with which others could lose weight (e.g., "If people just stopped putting food in their mouths, they'd lose weight"---I agree, but tell me how to do the first part). I've made it clear that I am dieting, so that means, that some things might change. I will be getting my 20 minutes of exercise in a day, no matter what. I may not be able to go out for a drive to get an ice-cream at night on a whim (we can still go out for a drive, though). I've learned that I have to stand up for myself.
4) Find a maintenance plan that you can live with. I'm currently dieting strictly because I'm impatient to get some initial weight off more quickly (I need to in order to get motivated), but I've already mapped out what I'll be doing for maintenance this time (something I have never done any other time I've lost weight). I plan to do the No-S plan (Google it), i.e., eat three reasonable meals a day---no snacks, no seconds, and no sweets----Except for Saturday, Sunday, and special occasions (birthdays, holidays, etc.). (I plan to have my treats on a weekday and on Saturday instead of Sunday). This plan is doable because it requires no special foods, no special preparation, and I don't feel like a freak by turning down birthday cake at a birthday party. Also, it's the way Americans generally ate 30 years ago before the dieting craze hit.
5) Finally, --and this may be the most important---don't focus on the unfairness of your plight. I get caught in that trap often. I'll focus on how unfair it is that others can eat "whatever they want" and still be thin. What you'll find is that the main difference between "naturally" thin folks and people like us is the desire for food. I honestly believe that people who struggle with their weight genetically have a higher desire for food than those who do not. Once I realized that and accepted it, I realized that because of that, I would always have to be more conscious of my eating than many other people. Do I wish it wasn't so? Sure---but I can't change reality. It is what it is, so I must deal with it.
I wish you the best. You CAN do this.
Good luck at getting back on track!
sad I know. This crap keeps happening to me again and again. I think I love food too much. I put the weight back on due to inactivity and eating out all the time with my Skinny Beautiful Wife (110 pounds) 