Honesty from the people that love you goes a long way too. rather than ignoring the problem, if someone came out and told you the truth (provided it was not a medical issue, but lifestyle etc) then that works, at least for us.
Rather than the "I love you the way you are" or "sure, those pants look great on you" thing, if my wife puts on an extra pound I tell her. "I know you can look better and be healthier" really works.
Once...she asked if we were going to dinner and I asked if her ass was invited too! Okay, so she beat the **** out of me for that one, but constructive stuff really works.
She does the exact same when my gut starts to venture out before the rest of me too.
We both run every day and even if it does [edited] her off or she me, then I get extra motivated to run that much harder that day.
The biggest benefit, is that our kids (6 and 7) see what we do every day and somewhere somehow it is being registered in their little minds the importance of exercise and lifestyle and its effects on stress, our relationship, tolerance, job performance, and overall happiness etc.
PS- Mackie and brandt, skinny and young does not equal promiscuity. I believe that healthy mind and soul equals happiness and fulfillment equals less promiscuity. It has nothing to do with fat.