I'm sorry that happened to your friend. It must have been very scary.
I saw a few Youtubers discuss traveling with their love bracelets and most of them bring the screwdriver with them when going through security at airports just it case it absolutely has to be taken off.
I usually wear long sleeves so no one really sees or notices my love bracelet. I'll only show more or wear more jewelry when I'm with my husband or when I know I am in a relatively safe environment.
If I really feel the need, I'll twist my wedding band and E-ring so that they face inwards into the palm of my hand. That way none of them sparkle or attract any attention. neither of my wedding rings are full eternity stones, so they'll just look like 2 metal bands.
Pickpocketing has been relatively well known throughout parts of Europe for years. I haven't been to Europe 2019 (last time was Greece and Albania), but if anything, I'll make sure to not wear as much, keep my guard up, and hope for the best!
Note: I travel relatively often usually with at least one friend, but I have traveled alone before. And I've found the best way to not attract attention is to dress very simply/plainly. I have no logos, no bright colors or tight clothing that shows a lot of skin. I tend to not wear makeup. I usually have a fake wallet in a purse with small cash/bills. If anything, I'll throw it to them and run. (I wear sneakers or flat shoes so that if I need to run I can.) The real wallet and my passport is in a more secure area on my person.