He regretted the last couple of days, that he knew. The only problem was that he didn't know what he regretted. Perhaps attempting to save Tain was an idea that was naturally bound to have a devastating end. After all, wasn't that always the way it had worked for him? Not to say that being Enabran Tain's son did not have it's advantages, it was the reason for his success through out his many years on Cardassia.
Unfortunately it was also undoubtedly the cause for his exile. Tain could choose whatever reasons he wanted as a excuse, but there is always truth within lies and Garak had no doubt in his mind what that truth was. He was a weakness, something that could lead to Tain's downfall and because of that he had to disappear.
Maybe Tain had been right about him. Maybe today was nature's way of testing that. The chance to gain back everything that he once was, was put on a silver platter in front of him and he did accept it however when he was asked to interrogate Odo, he hesitated. It's not like he never tortured people who were close to him before. He had killed people who were his childhood friends and never felt a hint of sympathy. He had looked into the eyes of his friends while they begged him for death and continued to torture them in ways their innocent minds couldn't dream of.
It had changed this time. The apathy that once came so easy to him was gone. He hardly knew the changeling and yet he couldn't stand to watch the terrors he was causing. He should have been able to do the interrogation easily. He didn't even have to do anything but wait for Odo to disintegrate. Why was that so hard? Did being exiled really make him that pathetically weak?
Either way it had little meaning now, he could never go home. He had lost that chance. He would never fit in here either. He could make friends, perhaps even find a lover, but they could never understand what his life was like. Everyone was so full of innocence here. They would never understand the horrors he had done or the ones done to him. He would be lucky just to be with another of his own species on this station. It was not like the Bajorans had any plans to make friends with him anytime soon. Even if he does manage to adapt, that will only make weaker and that proves exactly what Tain thought of him. Either way his father wins.