In being there when Colton died, both adult Kat and Alice can't help but feel guilty in believing that they each were the cause of what happened. Elliot, the voice of reason, has come to the understanding that what has happened has happened and would not have changed. In this understanding, Elliot comes to some realizations about his own life in relation to Alice in his teen life, and what they went through together with teen Kat. Still, Alice knows she has to be at Colton's funeral to support teen Kat, something that adult Kat knows in remembering back to the time. Adult Kat, however, doesn't want to tell Alice the further extent to what she knows about Alice in that past. Adult Kat also has to reassure Del about Colton's love for her knowing what she knows about the woman at Colton's funeral. In present day, Alice may provide that much needed touchstone to Colton for both her mother and grandmother.
—Huggo