Hello !!

So, this is my version of the crime :

It seems to me that this woman in red is totally innocent:

The deceased was an alcoholic. So , I think that on Christmas night, after he got really drunk, this poor man suffocated in his own vomit, while the lady was putting on her make up upstairs.
When she finally decided to join her husband, she saw him from the top of the stairs lying on the rug. So she turned back to her room to phone the police and take her gun, thinking that there was an intruder . She went down the steps to be near her husband, she found him dead, stinking of alcohol and vomit.
The poor woman lost her reason, and became suddenly victim of an obsession: she had to open the presents.
When the police arrived, they found the lady still opening the presents and singing "I wish you a merry Christmas".
This is a sad, sad story.