Do you even know that wallet addreses can be similar a little bit,  base on what you said there is no way you can see the btc sent and your balance at the same time to be zero, and there's no way you can be unable to send it if you truly sees it in your wallet,  you have theacess to you private key,  and if I may ask did you by any means reveal your seed phrase?

Secondly,  this your case calls for a serious  security consciousness  because you might be dealing with fraudulent individual smarter than you, and lastly I don't know the kind of relationship you had with the person but I doubt an ordinary friend will just send you 1btc this calls a suspicious  alarm.