we do not share your data with anyone and there are many ways to control the visibility and storage life of your data here.
but the internet is a public space and you should always assume your data could be compromised.
be smart with your password, use tor or a vpn, and use pgp for sensitive communications.
I know there are folks on here who are ninja experts here, I just wanted to say I had no idea sites actually did this? My take would be to get a secure wallet to hold your coin, like coin base or Paxful etc→