Lucy starts out this letter thanking Mina for her sympathy, but she herself seems to be a fount of it. She feels so badly for the two suitors she has to reject. She not only cries in the moment, but after the fact when she thinks about them again. She laments that she couldn't agree to marry all of them - not even because she seemed to really love all three, but simply because then they wouldn't have to be sad.
However, as much as I do believe Lucy is a sympathetic/empathetic individual who clearly feels things very strongly no matter how little she can express them at times... I think there's more going on here. I think she is self-critical and feels guilty about not being able to please others. Both are traits that seem to go along with her role in society and the likely expectations for her socially: to be pleasant and socially adept. I imagine her mother has taught her how to control her own behavior first. There are several little lines supporting that later on, and also their whole relationship just is suggestive of the roles they feel like they have to embody.
There are a few lines which make it clear that a little part of her is enjoying getting three proposals in a single day. Not in a cruel way, but just kind of an exciting ego boost that you kind of want to giggle about with your friends. But she feels that would be wrong to do too freely, and certainly doesn't want this gossip to spread beyond Mina, because she cares too much about the individuals involved. In fact, another aspect of her tears this entry that I don't think gets enough focus is her sadness at the loss of two friends:
Being proposed to is all very nice and all that sort of thing, but it isn't at all a happy thing when you have to see a poor fellow, whom you know loves you honestly, going away and looking all broken-hearted, and to know that, no matter what he may say at the moment, you are passing quite out of his life. My dear, I must stop here at present, I feel so miserable, though I am so happy.
Even though Lucy clearly didn't seem to view Seward in any romantic light, even in a "what-if-I-weren't-already-in-love" way (her "what-if" for him wasn't for herself but rather for Mina), she definitely seems to have liked spending time with him. She liked him as a friend. And she feels so certain that in rejecting him she has lost this friendship that it upsets her to the point she stops the letter altogether for a while. Quincey made much more of a point of emphasizing that he would be her friend for life and that was a good thing, and she didn't write an outright denial of that one, but she still felt deeply upset about it.
snowghoul
germansingergirl
romaincrisis
stormborns
gummygunk
turnnoffyourmind
