I'm just going to assume that you actually care about this woman and are just worried about her associating you with negative stuff.
If that's the case, you'll want her to get out anything that's negative and then shift her mood. Otherwise, she'll hold onto the negative stuff and be more likely to associate it to you.
One way to do this is to let her vent... don't try to fix her problems or anything like that, just say "that must suck" or "I understand" or "that sounds really tough." And then go to shifting her mood to something better...
"You know what I bet would make you feel better..." and then give her the deep dick... or spin her around... or be playful with her... or talk about something she's excited about that's coming up.
Shift her focus. You can try doing that without her talking about her day or what's going on with her if you want to but negative stuff isn't bad... it creates a bonding between people.
I was in Iraq back in 2004 and saw some pretty fucked up shit then... the guys I was with all created really powerful bonds with each other because we felt like we went through it together.
If she feels like you're going through some painful things together and she comes out the other side, it's better than just having a simply "feel good" artificial relationship.