If you play a character you consider honourable and who is aware of the recent diplomatic development, then he should not forget Melhed's betrayal.
You're still approaching this from the viewpoint that the absolute truth of what Melhed did is wrong. That there is no other possible viewpoint, and that *everyone* must see it the exact same way. If they don't then they're dishonorable.
That's just not the way it goes.
The things that our characters do need to matter to other characters, also those outside your realm. Else there is no point to this game.
Of course they matter. But they are filtered through what those characters know of the situation, and how they feel about the different factions involved. The result of all those filters and impressions is a multitude of different viewpoints on what is right and wrong. If everyone had the same viewpoint, then there wouldn't be anything to drive the conflict.
The fact remains though that if your character has been paying attention (and if he's been kept in the loop), he will know that they did break it, and they did lie. Pavel lied his ass off, Maya broke the treaty she signed only 2 months before. You can choose to let your character ignore it but it shouldn't be done with a shrug of the shoulders.
My character knows that Melhed broke a treaty, a couple details about what that treaty involved, and that Thalmarkin claims they signed the treaty knowing that they would soon break it. She doesn't have any proof about it, other than that Thalmarkin claims that's what happened. She doesn't know anything about any supposed lies that Melhed has told. Or anything about any lies that Pavel may have told. I don't know what anyone else knows, but it's quite possible that the only people that "know" that Melhed lied are people in Thalmarkin, and maybe anyone they managed to convince.
I would imagine the majority of characters know very little about what's been happening between Melhed and Thalmarkin beyond the big things like war declarations. The rulers probably know a few things. Some rulers undoubtedly more than others. But everyone knows that all rulers are biased filters. They present the situation to their realm in the way that they want the realm to see them. Assuming they even present this situation to the people in their realms at all. So, yeah, maybe Melhed lied about something. But who *really* knows, and who only knows because Thalmarkin is making that claim?
Now as a consequence of this opportunism, the only sensible victory for us has become total destruction. I don't like it one bit, but now that is the only choice they have given us. It's just not possible to justify trusting Melhed again, unless we lose and are stripped of choice. In other words, the extremist 'us vs them' mentality is forced upon us. And if you're all hot about perspectives, that's something that you shouldn't ignore.
If Melhed's actions make it so that you can't trust them again, then don't trust them. If that means you feel that you have no choice but to wipe them out, then go for it.
What I'm saying is that as a player, you have to realize OOC that what other people "know" is likely to be vastly different than what you "know".
And I'm not saying what the reaction of your character should be. If you come here as a player and say "so what" to this blatant a breaking of a treaty, I have to point out, as a player, that it actually is a big deal that should be incorporated in your character's view of Melhed. He can go and admire them for it if that's the way you play him, I don't care.
It kinda sounds like you do care. Maybe it's just me, but the majority of your argument here seems to be aimed at convincing people that Melhedis mean and nasty, and that our character's should despise Melhed for breaking the treaty.
If all you're really saying is that character should have an opinion on Melhed's actions ... Then I'm just confused. Of course they will. I don't know what made you think that people's characters would *not* have an opinion.