Welcome, henryanna! I know what you're feeling.
I think, like alcoholics, we have to do this one day at a time. If we say this is the year we're going to do it, it doesn't matter that much what we do today, because we have the rest of the year to make up for it.
Instead, wake up in the morning and tell yourself this is the day you're going to do it (eat healthful foods, eat x number of calories, exercise x number of minutes, etc. - whatever your plan is). If you've met your goals for the day, give yourself a pat on the back - if not, do it tomorrow. Focus on daily goals - focusing on the long-term result can be discouraging because it takes so long to get there.
Consider joining in on the weekly goals thread in the motivation forum. People post their weekly goals on Monday, report in on how you're doing, and encourage others.
Age 61, Height 5'9"
March 2010 145 lbs, Jan 2013 173 lbs
1st Goal 145 lbs 5/25
New goal 140