Sense of an ending can you explain please

[sprout44]

I just finished reading this and i think i did rush it along, despite it being a nice read. Can someone explain the whole point of Veronica having a brother? and was it her mother that had him much later in life. Had it anything at all to do with Adrian or do we know why he took his life.
Thanks

The conclusion we came to in our book club was that yes, Adrian & Veronica's mother had an affair, and she got pregnant.

We all thought it was a bit of an anti-climax tbh

Thanks, i would never have thought that, that shocks me; I was dying to know what was in the diary and why he took his life. I do not mind books that finish and leave you to ponder but i feel with this one i need to know a bit more. I wonder did he have feelings for Veronica or not, she did seem so hostile and strange. Also what wa s it about the mother warning him about her daughter and why leave him the money, blood money whats that all about?