Possible to change your entire life?

I am reading the secret. And no matter what you think of the law of attraction, I can't help but notice that to do what is required for that... I would need to take my life and turn it inside out. It occurs to me that much of the successes people have with the LOA is due to this abrupt change in their lives.

I would need to be:

1. Happy a lot. No or little negative thoughts.
2. Trusting.
3. Kind.
4. Unconcerned with my finances.
5. Grateful.
6. Basically, ignorant... knowledge isn't power... it is often misery.

Someone once said that innocence is the lack of knowledge.. and I can't help but see that here. People become happy and joyful and because, they are kind of regressing into they way they were when they were children almost. But, whatever works works right? My current life being:

1. Unhappy and consumed with negative thoughts.
2. Untrusting and guarded.
3. Kind of mean.
4. Ungreatful
5. Obsessed with information - after all knowledge is power... but there is no doubt knowing things makes me worry about them.

Is getting me on a first class ticket to misery town.

But here is the question... CAN I DO IT? I am 48, is it possible to change your life like this at this age?