Drugs are illegal for a reason. Making drugs legal just makes the problem worse; the reasons most drugs are illegal is because of the many negative side effects they impose on users...and others.
Voluntary rehab and counseling don't work. Permissive policies don't work. There are literally thousands of shelters beds empty each night in LA, SF, and Portland because drug addicts would rather keep their drugs and paraphernalia than have a warm, safe space. The rare rich person who can control their habit or the consequences of their drug use because they've got a wealthy family to take care of them shouldn't be the basis for determining policy for the hundreds of people who can't.
Forced rehab works. Imprisonment works. Losing custody works. Some amount of externally-inflicted mental pain is necessary to overcome addiction to serious drugs like meth and cocaine because without it an addict will never develop the mental fortitude to stop using.