I may be looking too much into this, but I think that the ship was partly to blame for messing up Victor. He was in charge of bringing up the memories, but he failed because he didn't know how to deal with scary human emotions that with them. Memories are emotional, which is why we remember them. We remember the emotions that are tied to memories, regardless if the memories are actually accurate.
For this reason, I don't think the ship was sentient. Although a funny character, it only cares about having to deal with Victor for the next ten years rather than caring about how much he's suffering. In the end, he contacts Martine to travel to the their destination. The ship is probably only does this because it doesn't want to be responsible with the death of a human, because then Asimov's robot rules (I'm assuming this applies). But that doesn't mean sentience, like we see in the I, Robot short stories. Victor was just a really fragile person to begin with, that needed humans to deal with him because only humans have the compassion.
Overall, I just really pitied Victor. I completely sympathized with what he went through because that would totally be me if I was in that situation. If the story continued, I wonder if Victor could be able to return to (somewhat) normal self, at least one that could tell the differences between reality and fiction. Our own minds can play a pretty convincing part in tricking us, like with illusions and stuff or those dreams that you have where you wake up and get ready for school but then you wake up again and realize you were asleep the whole time. And then you really have to get out of bed now.