You can change your vote in private. If you're worried about getting locked up and/or murdered by your wife after she has seen who you initially voted for, then you could set up a cron job to change the vote even if you're no longer breathing.
In addition, the same problem applies to paper voting. What stops your wife from demanding that you wear a hidden live streaming camera when you go to vote, so that she can see you really cast your paper vote for the candidate she insists on?
