I"m not sure what to do or how to handle this situation and I'm finding I can't get answers so I'm turning to this site.
I have a 19 year old "step" son. I put step in quotes because he is truly my son. He moved in about 3.5 years ago since he couldn't take his biological mothers ranting and ravings.
I've been in his life for 14+ years and the past 5 years we have become really close. He calls me mom and I do spoil him rotten(he chooses not to speak to his biological mom for relative reasons)
Lately I just don't know how to stay close to him and also stay out of arguments with him. I am trying to let him live his life and "sow his oats" but he and I have agreed we would be open about everything and communicate with each other so we CAN stay close and open.
Don't get me wrong, I'm not perfect and I do have a tendency to "go off" if I feel neglected by him or if he doesn't keep me posted on something... even for a day sometimes.
How do I break my habit of not believing him that he will talk to me. Where do I find the strength to NOT doubt him. (by the way, most everyone I've ever had in my life has crapped on me in some way or another and most of the time I try not to associate with those people) He's the greatest kid and he has been honest with me (most times, even though I've found things out later)
How do I get a THICK skin? Am I just some nut?

Aww. First off, I think it's nice that you're concerned about him, while many mothers (Not most, just many) would be annoyed. It shows that you really care about him.

I would say the main thing would just be to talk to him, and let him know that you'll be there for him no matter what he does, or what he tells you. Tell him that even if he comes to you with something that you don't agree with, you will still listen and work through it with him. My mom never actually said something like that to me, but the way we talk and the things she say let me know that's how she feels, and I feel like I can talk to her about pretty much anything.