No matter what race or alignment you are, the others will all turn on you eventually. The only thing the computer players really respect is your military rating. As Vegetius said, if you want peace, prepare for war.
Marshall summed it up best I think.
In my current game, I'm evil (no surprise

), with two other "evil" races, one "neutral", one "neutral leaning good", and one "good" race.
It was easy to form an alliance with one of the "evil" races, but the other evil one... well, forget it!
Nothing I do (paying tribute, gifting trade goods, adding more trade routes, careful not to place influence or military sb's near them) seems to get me farther than "friendly" with them.
Very frustrating indeed, and now my alliance with Drengin has broken off too. Since my military wasn't quite up to snuff, I really counted on their strong military to keep the others off my back.
But yes, in the end they will all come for you, and especially if they see that your military is the weakest link.