Using just the example given, I would conclude the writer is saying to the reader: "Two people had a conversation on the phone recently, and during it they decided to hold a funeral for a person named Tom on the current weekend from the narrator's perspective."
The past tense component ("We talked on the phone for a while. In the end, we decided...") seems more like a means of advancing the story without going into the details of the conversation, while "...this weekend" suggests the narrator is speaking about something that is going to happen.
Ultimately, regardless of what period of time in which the story is set, it seems the narrator is in his/her present. However, if "this" had been changed to "that" it would read more like what the narrator is saying could have happened any amount of time in the past (relative to the narrator's present).