In my humblest opinion, it’s a natural thought process that occurs after a beloved passes. It should get back to normal.
Iv’e heard once, there’s a Chazal (somewhere) saying ????? ?? ??? ?????, which seems to indicate that it’s useful, indeed healthy to have some ‘morbid’ thoughts, theses should be only as a last defense, when all else (mentioned there) failed. It is sometimes too destructive a force. If it gets in the way of Avodas HaShem, help should be sought.
Now to the pros….