Finally working

He's finally got off his ass and started working again. It sucks that he worked only a month at a gas station since we moved here. I have pushed, begged and given ultimatums with no results. He finally put his name out there and now he's getting popular again; tattooing and piercing from home. I'd hoped we wouldn't have to do this again but at least it's SOMETHING!
My biggest pros and cons to this situation:
Pro: His confidence is returning and with that comes his happiness which in turn makes me happier.
Con: I don't trust him not to cheat on me again, not to take an easy opportunity and go for it...
What am I supposed to do? I want him to be happy, it truly does make life better for the both of us. I just don't want to be taken advantage of more than has already happened. I don't want to come home and see evidence of something wrong, because if I do and I ask him about it, he'll always answer honestly...
I'm scared and stuck.
How can I make the pain and fear of being hurt go away? It's been over a year since he cheated and I still feel like he'll one day make me regret staying. I love him, I want us to work, I just absolutely hate living in terror of what he can so easily do to me and my heart...