I feel for you...my BEST friend had a bad marriage and he tried to make it work because he's got kids. When the marriage finally ended (badly), he started going bad...
Now he's been strung out for 4+ years and i haven't talked to him in over a year. He doesn't have a phone that I can call him on, and he's been in jail (for robberies/credit card scams/etc) most of the time anyway...and it kills me....but there's nothing that I can do.
"...but uhh, a thug changes, and love changes, and best friends become strangers, word up...."