I fully agree that not telling her that I am still around was neither particularly smart, nor encouraging trust. And I did not know about that. I had assumed he had mentioned it, especially as he helped me with the move and continued to go to the cinema with me.

I also don't know what he said when he went to give me my keys back. "I am just returning OP's keys, be back in about two hours!" WTF?! is probably the nicest reaction to that on her part. She was probably pacing at her place for hours before he came back and I can only imagine what scenarios were playing in her head.

When we met at the station, I actually asked whether my friend had time for dinner, because it was Saturday after all, so girlfriend day, and I knew about her early bed times. And when he texted me later saying that he was going to his girlfriend's place, I just thought "Someone's gonna be mad, because of his late return."

Just based on what he explained to me three weeks ago, they had had a fight back in summer or so and she agreed (?) to the week/weekend split due to the fact that I would be gone soon anyways. With that in mind, not telling her that I am still around was probably done to avoid a new conflict, but yeah, it doesn't really help.

The last time, I suggested doing something together was during the party for the German reunification (October 3rd). I was at the big party in front of the Brandenburger Gate with two friends and asked my friend if he wanted to join and told him to bring the girlfriend, because at that point I didn't care anymore. They didn't come, because she didn't wanna go to the party. Again, I don't know how he asked her, whether he mentioned me or not.

So, after four months or so of what was "mildly peaceful co-existence" to me, still without meeting each other, but the week/weekend split seemed effective, her reaction came a bit out of the blue. Because for me, nothing had changed since October, whereas of course for her, EVERYTHING had changed. I can understand her reaction in a way.

So, my question about what I should do is not aimed at "What should I do to get him back?", but rather "What can I do to deal better with the loss of a good friend?" and also "Can I possibly make it easier for him?" It's kinda unavoidable that we will bump into each other at work every now and then and last week in the cafeteria queue he was clearly not comfortable with the situation.