I worry about this too. I store the database itself in Dropbox, and I also use a keyfile alongside the password to open it. I can easily recreate the keyfile on any computer, but it never goes anywhere near the internet.

In addition to that, for my really critical "gatekeeper" accounts, I don't put the full password in the database. Just a reminder that this is a "special" password, which needs to be combined with another bit of info in order to work.

I just live with the fact that I can't use this system on my phone, and for my usage patterns, that's fine. There's nothing I need to do that's so urgent that it can't wait until I'm back in front of my computer.

Why can't you use it on your phone? There are various apps for Keepass available.

On my laptop. I synch to my phone and tablet using Syncthing. I write into the file only on the laptop.

I keep my db in my own freenas box and sync it between devices using resilio sync.