Losing saltiness can be a tall order. But you are the only one who can make that happen, and it will only happen if you make a deliberate choice to not be salty.
Sometimes when I get into a salty rut, the only thing that will work for me is to take it one day at a time. Even that can feel too much, so I will divide the day up. I will put my feet on the floor when I wake up and I will declare (yes, out loud) “This morning I will choose to be positive, react positively to whatever happens, remember my place in the universe, and be open to the many blessings that come my way.” As a Catholic, you could try the same thing but replace the universe part with more of a statement of what you believe as far as staying close to God and accepting his blessings, etc. Personalize it to the extent you like.
It sounds so simple to say happiness is a choice, but if you think about the people you may know or have read about who live/d life under miserable circumstances but still were happy beings you realize it is possible. Certainly a challenge, but not nearly as challenging as living life feeling salty day-in and day-out.
I know what a struggle it is to have a new baby and such a full plate. I will keep you in my prayers that your return to work is smooth and peaceful.