I'm an otherwise healthy, fit cis male but goddamn I feel like any "oommph" I had before starting a workout gets vacuumed out. It might be motivation. It shouldn't be hunger. How do you deal with it? Roughly a quarter of the time I can "aggro" my way out of it and have a normal ~30m workout, but other times nah. Shit sucks.
Just do the workout whether you feel like it or not. Eventually if you don't often enough it becomes a habit and you stop thinking about whether you feel like doing it, so the issue goes away.
Also remember that it's better to have a less than perfect workout than no workout at all
the majority of my workouts are "stumbling to the finish line just so i can say i did it" but surely there are people who still enjoy working out, right?
If that's the case you should start with shorter or less intense workouts and build up from there. You should feel a sense of accomplishment when you're done and there's no shame in adjusting the workout length thats challenging but achievable
Are you following a program? You should be following a method that has been designed by a professional that will help you meet your goals. This could be from a trainer if you want it to be (I don't think it's likely to be important), but it could also be from a book or online resource.
Doing your own thing is just "exercise" while following a program is "training" that will leave you feeling accomplished as your performance improves week to week.