Addiction is a terrible thing. My step-daughter lied like it was nothing. She stole money from her father and I and once we figured out to lock up purses and wallets she started selling my jewelry and antiques and finally our CD collection (this dates me). I think she got fifty cents per CD...
She's been sober for 12 years. I even trust her now. I love her and think she's a great person.
There's a difference, I imagine, between the addict being your kid or being a spouse. People can recover. Forgiveness feels good. I have to admit at first my forgiveness felt like I didn't really have a choice but even that has changed. Her sincere recovery has made the difference.