Personally I'd be more concerned that your DP thought it was fine to go ahead and open a parcel that was addressed to you! I've been married over 40yrs and Mr MW has never opened a parcel addressed to me, especially at this time of year!
Duplicate present from a couple of years ago, storm in a teacup. There's the potential for a lot more hurt and upset being felt by your stepdaughter if she didn't know he already had the watch she has carefully chosen for him.
Humza Yusaf's resignation speech