I must say, this treaty cancellation has stirred up quite a bit of controversy, though anyone that knows me would know my position on this cancellation and on either alliance. Not exactly OWF sharing material though.
I can say this though.
Europa: You need to get your FA path sorted. While Schatt said it in a rather rude way, he was right in the fact that you can't just sign treaties on both sides of the web. It just results in you having to declare neutrality every time a major war comes along. Keep relationships from other realms separate to this one.
TOOL: It is rather uncharacteristic of you to cancel a treaty during a war. I'm not sure what to think of this.