Writing, then hating it, is normal. In his book Innovation on Demand Allen Fahden talks about the PEP cycle of creativity: Panic | Elation | Panic. It hits us all, and all you can do is wait it out and trust your processes and skills.
But when you can’t create, the solution is to refill the well. Spend time reading great books, listening to great music, watching quality movies that inspire you.
In her book Around the Writer’s Block Rosanne Bane describes the brain science behind play, and how spending time playing with no attachment to any creative outcome restores the creative circuits in our brain. Shaping clay, coloring pictures, playing a musical instrument just for fun.
Letting creative joy flow through you by taking it in and letting it flow out unhindered is the best way I know to fall in love with writing again. (And take a break from the work; don’t force it, you’ll struggle even longer.)