Diable

I'm having some trouble with Satan. The fact is, I have an insanely hard time believing in him. A harder time than before I believed in Jesus. It just doesn't seem right. -Aren't we the ones messing up? Not because someone was stalking us and trying to tie our shoes in knots so we fall? It just doesn't seem probable to me. Aren't I the one making the mistakes?
Because we are Christians is it fair to chalk it up to Satan whenever we mess up. I feel like when I was little. I didn't break the lamp....The devil did. He made me. Not that I think people can make anyone, do anything. We always have a choice. So I suppose its much better for me to say "he tempted me." I made the choice to listen to him however. I didn't have to. So how is it that you know when the devil is influencing your thoughts, or is it God. I know it might seem obvious to know the difference, but lets say that you have this great job, and your boss tells you, that do move up you need to move across the country. You go to consult God and you swear he keeps telling you not to go. But was that really God talking there? Or is Satan trying to keep us from our dreams. You could decide that's what happened. That you really should move. But then there's the wonder if, what if it God. What if the plane crashes that I'll be on? Or maybe when you arrive you find that your new position in work doesn't fit with your morals, that you have to compromise who you are to work in your now current conditions.
I guess my main question is; how do you who's who? Who's playing God and who's trying to ruin your life.