Being jealous of your best friend doesn’t make you a bad friend. What you do with it decides that.

Envy toward somebody you love is uncomfortable mainly because it feels disloyal, so people hide it and then think badly of themselves twice over. The feeling is close to automatic: they got the thing, you wanted the thing, and your nervous system registers that before any of your values get a say. What you do in the following hour is the part that is actually yours.

Congratulate them properly, out loud, in the first few minutes. Then take the envy somewhere private and ask what it is pointing at, because it usually names something you want.