I didn't understand the reference to Doggett's face in the war room, so that makes it clearer. (And now that I think about it, of course. He also lost a child.)

The plans to kill herself were very obvious to me. Especially "It wouldn't be so far down" when she's looking down at the ducks in the icy pond. And for me it infuses the whole story: she has to fulfill this last responsibility, telling Mulder, but the utmost importance in her mind is reserved for the place she has to be.

"I'm coming" is an interesting line--there's several mentions of coming and going. Mulder's note to her says "Please come", at the end she says "I have to go".