I absolutely understand what it is to be lazy. I'm unbelievably lazy myself. Yet I've been able to get with (and stay with) a weight loss plan for three months and change now.
For me, the key was to make it require
more effort to eat off-plan than to stay on it. It's precisely
because I'm lazy that I've made it easy on myself to stay with it. When shopping, I pretty much skip the center aisles as all the stuff I want is on the outer part of the store (produce, meat, dairy stuff); being able to do this appeals to my lazy nature. I'm also so lazy that when I cook, I cook big amounts so I can store stuff; that way I can skip cooking here and there. As for fast food/prepared foods, I'm so lazy that I can't be bothered to drive there and place an order when I could just eat something in my own kitchen. It's a lot closer than McDonald's.
Laziness also means not a lot of formal exercise. I can rarely stir myself to do it. What I
can do is walk to the store, walk around the block a few times while I think of work stuff, and walk with my husband because I like him. I can also ride a stationary bike while reading instead of loafing on the couch while reading; it's marginally more effort, but once I'm on there, inertia keeps me going. And I can lift weights because it's kinda fun to do. Maybe for you, dancing would be fun. Maybe Wii Fit is your style. Maybe you enjoy gardening. There's almost certainly some kind of informal physical activity that could become exercise if you did it longer or put more effort into it. Try new stuff; you might find you like it like I found with my free weights.
In addition to being lazy, I'm also broke. That means we eat a lot of beans, big inexpensive cuts of meat, whole chickens that I or my husband butcher ourselves, and fresh fruits and vegetables. Locally grown produce tends to be cheaper, as does stuff in season; It's a happy accident that these are also great-tasting; mostly we buy them because they're cheap.
My weight loss isn't super fast; a lot of people have lost a lot more than I have. But I'll take my seven pounds or so a month and keep at it, because getting over a quarter of the way to my goal is pretty good for someone as lazy and broke as I am.
Motivation may not be what you need; routine and inertia may be what you need. It's been working beautifully for me.