Dieting and exercising plans

Today I'm pondering the word "diet" or the word "weight loss" . I've started growing concious about my weight. The reason I say this is because I had a supervisor at work the other day tell me that he thought I was gaining some weight. Well, to me, It's a no-brainer. I know I've gained some weight. It's obvious from the spare tire sticking around my waist line. I see it in pictures of myself and my doctor years ago told me I was 20lbs overweight. It's hard for me to face the fact that I really need to lose some weight, not just because I'm overweight but, because I have heart disease. I have to say it's not easy losing weight. I used to look at all those big heavy people walking around and I would be laughing wondering why they were so big and why they couldn't lose weight. But now I have a little understanding of how they feel. My wife and I were going to buy a treadmill some time ago but a good friend of ours had one they weren't using and gave it to us. We put it in our bedroom and for a few weeks we used it just about everyday. Now were lucky if it gets used once a month. I work the swing shift and get home late about 11pm at night. Most times I'll come home and eat a regular meal and then brush my teeth and go to bed but I heard it's not good to eat so late because the food just sits in your stomach and doesn't digest. Sometimes I'll come home and just binge eat for now reason. My wife has started to eat more healthy but I think I'm dragging her down with my less than perfect support. I think it's a lack of motivation and effort on my part. I think I don't want to go on a diet for fear of failing. Does this sound right? Probably not but that's my excuse.