I didn't know it had a name. I've definitely experienced it. At university, with an older, very charismatic man, who made me feel more alive than anyone I've ever met, for the brief time I was with him. He was exciting, unfettered, and quite gorgeous. He was also bereft or morals or ethical considerations, deeply selfish and quite unhealthy. I last saw him around 15 years ago, and of course the feelings have faded almost completely, but I think for at least 5 years after I thought about him every single day. I am grown up now and I understand that it was not a relationship and never could be, not in the real sense. I adored him, and was addicted to the way he made me feel.
I used to sit in a certain place in the library where I could see the street that I know he would have to walk down on his way in. I used to walk past his flat even though it was not directly on my way home. I didn't actually stalk him, but in the infancy of the internet, I used to scour professional journals for the mere mention of his name (just seeing it on the screen would give me a frisson). I remember the intense thrill of ordering a book from the stack and finding an old slip in it with his writing. I dragged my friends around every pub in our University town to find him one night when I knew he was around.
It was a strange feeling. I don't regret it, because it didn't have an adverse effect on me. He simply drifted away. If he had been a worse person he could have ruined me, I know that now. I snapped out of it and got on with my life, but I well remember the all encompassing obsession where everything was him him him him him.