[Nyororin]

She was given the option to come to the police and have urine testing done to clear her of suspicion of use. She was separated from her husband, and the only thing they had to go on to suspect her was his saying she did. Police asked her to voluntarily come to them for testing.
What did she do? RUN.
I think that makes it pretty clear that she was also indeed using.

She also took her 10 year old son who later could not be found. Tracking her cellphone put her in serious countryside and mountains... An ideal place for a suicide. They had EVERY reason to panic and search for her.

I don`t see why they should look at her son for this. In Japan, drugs are not out and about where kids can get them. Especially not 10 year olds.