Remember that you’re only a few months out yourself. There’d be something wrong with you if you could just feel that magic again right out of the gate. In fact there’s even a name for that, isn’t there? It’s on the tip of my tongue... .
Dogman, the term you are searching for is limerence:
A state of mind which results from a romantic attraction to another person and typically includes obsessive thoughts and fantasies and a desire to form or maintain a relationship with the object of love and have one's feelings reciprocated.
The bit missing from my r/s with my ex was reciprocation.