Thank you guys for the feedback. T got the news we were hoping against. Her bf (8 years+) has metastasized cancer. It's already in three places. This is in addition to other real life stuff going on.
We hung out a little last night, and I'm pretty sure it will be fine. She's very understanding and even with the above going on, she apologized for interrupting when she called. Her bf's life is in danger, and she's worried about pulling me out of a different conversation. So, she will be understanding if I feel I need to pursue other relationships. That's still not a given, but I do feel less guilty about it. I often need to remind myself, she's a strong independent woman. It will bother her more if I try to hang around her like a lap dog.
Also talked to K. Made sure I wasn't neglecting her and made it clear that she's under no moral (or any other) obligation to suppress her needs/desires on account of T's issues. She said she was fine, but she looked visibly relieved when I said it. Of course getting her to vocalize her needs is a different story.
We're going on a 10 day vacation without kids next week, so we should be good for a while regardless