Zeke was your "Spirit Animal." So you had a very unique bond. Eventually your new dog will also develop a unique bond with you, as every dog is unique in it's own way. Having had 15 dogs, you already know this.
Just be gentle with yourself. And try and not overthink, or over analyze all of your emotions during these difficult times. Grief is like the tides of the ocean. At times it is a small swell, that will ebb around you, at other times it will almost consume you, rise up to your neck, make you panic, and then at other times it will completely overwhelm you and almost drown you ( in sadness.) The trick is to just "go with the flow" and not try and fight the negative energy of grief. Tread water when necessary, swim gently when necessary, or hold your breath, until you can breath easily again. Don't panic. Stay calm. Stay at peace.
I am sorry for your loss of your beloved Zeke. He must have been a very special dog to have impacted you so deeply. That just shows the depth of the love you had for one another, and thus...the depth of your current grief.
"This too shall pass."
Kind regards and my sincerest condolences,