This happened to me a lot of times. Relatives used to borrow money from me and out of mercy I lend them my hard-earned money but they didn't pay me and they are even ignoring my texts and chats. From my experiences, I learned to say no and cut ties with abusive relatives. You did the right thing because that's a huge amount of money especially if that relative of yours isn't trustworthy. When it comes to money, we can see the true colors of the people around us. You shouldn't be the one to feel awkward because you just saved yourself from stress.
That happens with almost everyone since all of us have that kind of relatives who borrow money by becoming innocent at first and then don't even answer your calls and messages. The only way to avoid such people is to simply say no at first by making some excuse because if you don't make an excuse, they can become very toxic later on.
Never lend money to people who you know would never return your money, at no cost you should compromise your own life and self-esteem for someone else no matter how hard they try and how many times they ask you innocently.
Best to say no always especially if they borrow just for the sake of unimportant matters since its really hard to have bad blood to your relatives if they refuse to pay on agreed date.
Its really good for us not to lend to anyone even if this is our close relative so that they can establish the thoughts that we are not into that and we will never lend money to anyone. But also we also need to take some consideration like important matters for example immediate medication and that maybe we can consider and think only that we give it to them so that there's no hard feelings for us if they will not pay the money we sent to them.