When Titus doesn't tell Violet about his friends going mal, he feels he is protecting her from something. Why is he so bothered by their actions?

Titus, like Violet, understands that the group has been through something large, although it is not until he hears that Violet is damaged that he understands how large. He knows that, to cause a malfunction in the feed is to risk permanent damage, and they have just experienced life without the feed. After Violet's revelation that her feedware is still problematic, he is even more disgusted, as he knows Violet is damaged, and his friends are paying to go through similar damage.