I had a chameleon and let it go into the wilderness for a better life but sometimes I still picture him crawling around?

First, I don't think it really matters what that means. 

Second, don't release pets into the wild. Even exotic ones that are not domesticated. They die/cause problems in the ecosystem.

Third, before buying or adopting a pet, please do research first. It is important to take responsibility for all pets and re-home them if you can no longer care for them if your situation changes. Don't just release them to the wild.

Maybe you feel guilty about leaving him to fend for himself.  I hope you released him in an area where there are other chameleons so he has a chance of surviving. 

Your chameleon either perished quickly as it was not used to fending for itself.

Or

If it survived could have disrupted the local ecosystem.

In neither case was it living a "better life" and of you still picture him crawling around it is purely your imagination, not a psychic connection.

That he made a bird a nice snack. 

You feel repressed guilt for turning a non native species into an unsuspecting echo system.....

Like the jerks that let loose their non native snakes... what could one snake do....  hoe could it possibly ruin the eco system.... in ten years it lays over a thousand eggs that hatch, in turn that same snake is responsible for over  100 thousand offspring, great great great great offspring etc.  remember that there’s no stopping species especially when they cross breed with a native species.

Same can be said with any reptilian species.

Why didn’t you just donate it to a zoo or a reptile center like an intelligent human being rather than a stupid childish action.

Your dream is your guilt weighing in your mind.

Don’t ever get a domesticated dog or cat, they don’t want you to turn them loose in the wild to fend for themselves.  I could see it now, a whole feral pack of peekanerse dogs hunting down a deer...., not.

It means you're feeling guilty about releasing a domesticated animal into the wild where he can't fend for himself.