It is so easy to get used to our routine that the mere thought of changing can be quite scary. It is so much easier to stay in our current condition, no matter how unhappy we are, and say "well someday I plan to X." That's far safer than actually doing X.
I think a key is to take a small step each day. Don't put it off. Don't talk about doing it tomorrow. Just do something today. Do something the next day. Get that progress going.
We all have our challenges. They are just one part of who we are, and they, like our brains, are able to be changed.