What's up with Linda in Halo 5

Does anyone else notice that Linda was focused on a little bit? In the trailer a while ago with Chief died and Linda was focused on and she picked up the rock off of chief, and at the end of Halo 5 when cortana appears Linda steps in between chief and Cortana and chief has to put his hand out to stop her? What was with that, not complying just wondering. Or am I just going crazy?

In the expanded universe, Linda basically died in chiefs arms and he immediately shoved her in a cryo-tube, and she was revived later. besides being life long friends, she essentially owes him a life debt.