Welcome to Spark People !!
I'm going to give you one piece of advice that I give to all new members and it's this,"don't look at weight loss or good health with an all or nothing mentality". If the only healthy thing you were to do for yourself today was drink 8 glasses of water, that's still a step in the right direction.
Remember, you're trying to change habits learned over a life time. That's not going to happen overnight, a week, a month or even a year. Change takes time. Thus the need to be patient with yourself and your body. Don't listen to those negative voices in your head. Listen to the POSITIVE ones !!
You can't change the past, but you CAN influence and change the future. One small change can change your life.