It really doesn't matter whether a person is totally out of shape or close to their ideal goal, working out and keeping to a solid nutrition program is hard work. Sometimes my husband and I go downstairs to workout in the evening and both of us don't want to workout. At dinner time one of us will ask if the other is working out tonight. I'll say "yes, even though I don't want to", and he'll say " I should workout and most likely yes". It's one of those conversations that comes up now and then. I think we do it, because one person is really not feeling like working out, and wants an excuse not to workout, but ultimately it seems that each of us makes the right decision based on what we know is right for ourselves, not because of what the other person says. There are many times when each of us has gone downstairs by oneself to workout, because the other person has decided not to or it was a day off.
Sometimes I count the minutes while on the "dreadmill". I love my treadmill, but sometimes it really is dreadful. The minutes slowly go by as I run. I get to 15 minutes and I tell myself, "I have 15 more". At 20 minutes I tell myself "that's not so bad, only 10 more minutes to go". Without fail, after I finish the treadmill, I'm all happy again. These types of days are not typical, but I wanted you to know that I am no different than anybody else in this respect.
...however, giving up and giving in is NOT an option.