Sorry for your loss.
I've not interacted enough with the user to be able to make any sort of judgement on them but they have had a history of successfully repaid like and before this.
I hope you can recover from the loss and it doesn't affect your service going forward.
I can't speak for all of them but I believe that this kind of people are after the quick bucks instead of long-term money especially in this forum, we just have to understand that not everyone likes to post in a forum about stuff related to the theme of the forum everytime.
They wouldn't hang around for close to four years and make over a thousand posts if they planned to make away with just over a hundred bucks.