Yes, I would definitely say it's normal. When something destructive becomes a habit, it soon becomes an addiction.
I've experienced this
SH addiction many times. It's meant to be a 'quick fix' for any problem. But ends up backfiring.
When you get accustomed to using the 'easy way out,' which essentially, is what
SH is (not dealing with the problem at hand). Then it's easier and easier to take the easy way out for smaller and smaller things. Eventually you won't even need a reason at all, you'll
SH just for the purpose of
SH. Addiction is addicting.
I hope that answered your question. But like others said, you might want to consider talking to your friend and try to convince her to get help.
Take care,
<3 Boxy