In my most recent game I was playing as the Torians. I had conquered the Yor and the Thalans and I was allied with the Terrans and Drath. The only remaining civilization was the Arceans. I was going for a Diplomatic Victory but I could not ally with them. Alliance was not an option under treaties. Both our attitudes were Friendly and we both had Alliances. Ultimately I ended up just researching a technology victory while all my allies watched. Has anyone else encountered something like this? Is it a bug, or something with the system? I think I remember it happening before also, but in that game I probably conquered the other civ (or quit out of frustration).

-Nero