How biblical is this statement?

I’d say it’s good to be thankful, whatever the reason, and to be content whatever we have or don’t have.

1 Thessalonians 5:18-Give thanks in every circumstance, for this is God’s will for you in Christ Jesus.

Philippians 4: 11 I am not saying this because I am in need, for I have learned to be content whatever the circumstances. 12 I know what it is to be in need, and I know what it is to have plenty. I have learned the secret of being content in any and every situation, whether well fed or hungry, whether living in plenty or in want. 13 I can do all this through him who gives me strength.

If something like that is in the Bible, you might check Proverbs or Ecclesiastes.

It's fine, although I would change it to this: "Sometimes when you lose something, it is a reminder to thank God that you have Him."

I think it is runs the danger of papering over the depth of some folks' grief and trauma. If I lose a jacket, sure. If I lose my scholarship, that's a whole nother.

I think the way it is worded could be a bit problematic. Some people might interpret it to mean that God caused you to lose it since you weren't appreciating it.

But I think if you understand it as a simple reminder to be grateful for the time you had it rather than upset over losing it, it's fine.