What is the theme in Amsterdam by Ian McEwan?

One major theme in the Amsterdam is euthanasia.... personal choice or assisted death. After witnessing Molly slowly deteriorate, Clive requests to be euthanized as to avoid a long and painful death. Vernon, another of Molly's lovers agrees and asks the same. Over the sourse of the novel, we see euthanasia redefine itself as a method for murder.... opening the use of euthanasia up for debate.