Since 5.12 champ select freezes and d/cs

Ever since the 5.12 release i now cannot play, have lost lp, and getting absurd penalties because the client continues to freeze then crash or simply stays that way until my team has all picked and it d/cs me for not picking a champ. REDS PLEASE HELP. Ive spent nearly 3k$ on this game since beta, and would like to be able to play if you dont mind.