Crashing and then client not relaunching [Crash]

So I queued into a ranked game, got into champ select, and when the loading screen was supposed to show up, nothing just black. Ctrl+Esc did nothing, so I gave it about 5 minutes and with no progress, restarted my PC. I was able to open the client back up, but could not reopen the game. I honestly feel terrible about this and would like to know how to prevent it in the future.