Unhealthy obsession with crushes

[Mybesthasneverworked]

Whenever my DD15 has a crush her personality changes in a very negative way. She becomes obsessive about the boy, angry with everyone, makes awful comments to me and even her siblings, she ditches some of her close friends many of which have never repaired the friendship, gives up on her school work and spends all day on her phone either talking to the crush or finding out anything about him.
This is the third time we’ve been through this and I’m sick to my back teeth of it. When she has no interest in a particular boy she is wonderful, no attitude, does well at school and focuses on her friendships.
The last 2 times went wrong, the first crush didn’t feel the same and it took several months for her to feel herself again.
The other time resulted in a relationship and the obsession became even more intense, she’d send him love letters daily and plan their wedding. All typical teenage fantasy stuff. But it scared him off.
The current crush complimented her at school and now he’s her world, despite him not being ‘her type’.
I know this is what teenagers are like but I’m concerned about the obsessiveness and change in personality. Is this something best left alone or does it seem a bit more than just teen stuff? I tend to leave her to it and make sure she knows she can come to me about anything, but any rudeness she will be called out on in which she’ll play a victim.
I’ve spoken to her about it before and she refuses to accept our version and accuses us of attacking and bullying her for liking a boy, which isn’t the case. I’m just worried that she doesn’t see crushes/relationships in a healthy way and she could end up in disastrous situations as an adult.
I know I’ll be asked this but I’m not with her dad, we split 10 years ago and we get on well, she hasn’t been exposed to anything negative or traumatic like watching abuse/a nasty break up etc. it was amicable and she doesn’t remember much of it, she’s had a good childhood and gets on great with my husband (her step dad of 7 years)
Any advice please?

I remember the intensity of teenage crushes but this sounds way over the top.

I have no relevant experience so other posters might have better advice.

i think you’re right to be a little concerned. Has she ever been like obsessive about other things? Is there a school counsellor you could speak to?

during peri, I had something resembling a teenage crush. It seemed all consuming, but didn’t affect my work, friendships or social life…just made train journeys interesting time for day dreaming

This sounds familiar to me, I think it is linked to depending on someone else for self worth, it is a fantasy starring a different version of herself in her mind and it doesn't matter who the co star is as long as they like her a bit.

The obsession is rooted in looking for evidence to prove that this new crush really is her soulmate and twin flame.

Because she doesn't much like her current self. Does that make sense

It sounds like dopamining to me; your DD is mistaking the dopamine hits she gets from texts/communication/attention for love.

I was the same as a teen (before phones etc) and I now recognise I was just addicted to the dopamine of teenage relationship ups and downs. As soon as I was bored or had the 'ick', I'd dump the boy and move on. I think lots of teenagers are the same.

It might be ADHD-adjacent or it might just be her way of 'feeling' something.

It does sound intense and I would be worried too.. does she have hobbies, interests and good friendships? I wonder if there is something you can do to encourage more healthy pursuits.

Having said that, it isn't always that simple...out of my 4 the one who always dated and dated very young was by far the one with most friends and hobbies... so the two don't necessarily go hand in hand!