Love is an emotion, so dividing an emotion into "real" or not isn’t very useful here. Love is also an action. The action determines whether or not the emotion is detrimental.

An example?

Obsessive love feels very real to the person on the giving side of the experience. Not so much on the receiving side of it.

I would definitely say that it’s unhealthy because it’s so maladaptive. Fear (usually of loss or rejection) drives the lov-er to suffocate the lov-ee to the point of bringing about the very thing the lov-er fears the most. The lov-ee is forced into hurting the one they loved and cared about as a means of self protection.

There are lots of ways love can be maladaptive, but it usually boils down to either another strong emotion coiling around the love emotion like a vine that strangles and warps the love emotion or negligent gardening, one or both parties fail to tend to the love emotion until enough weeds (daily grind of life, past trauma) have popped up and taken over, the love emotion dies. Funny thing is, using the gardening analogy, if you and your lover are representing two prize winning rare flowers in a garden, you have to water your own flower but keep the weeds off your lover’s flower.

Anyways, that’s my 2¢. I might of stumbled into some profoundness on that one, or maybe not. Hard to say.