Excercise Help Needed Please

I know I need to start excersing.  I belong to the gym at my job and I was doing very well with going 3 times a week at lunchtime.  I was so diligent and excited when I first joined.  Then, as with anything (at least for me), I just stopped going.  Why?  Well, I could come up with every excuse in the book.  The true reason is that I just got lazy and fell off the wagon.  Now, for the millionth time, I am back at square one where exercise is concerned.  My question is, how do you keep yourself motivated to stay on track and not get lazy?  How have you come to the place where exercise is a daily part of your routine?  Or, are you in the same boat as me?  I need suggestions and thoughts, please.  Unitl next time, stay strong and eat healthy.