Obsession with teacher and how to redirect this

I believe my daughter has an obsession with one of her teachers. I'm not too sure if it is quite an obsession or what it is but we've been in this position with a different teacher. It might just be she feels safe with this teacher and enjoys the company or if it's something more. 

Both these teachers live close to us and she knows where they live because we constantly drive past their houses to get to where we need to be. Also both these teachers are female. 

She follows this teacher quite regularly to and from school because she likes to leave early so she can get parked in the car park and also so she can chill without being stressed and worried about traffic, parking and being late. At home she also talks non-stop about her. 

In school, she really enjoys spending time with her teacher, and will struggle to complete work and just want to chit chat about her teacher's family, dogs, traffic, and what's on her mind especially. She also engages with a lot more SIB with this teacher, I'm not sure if it's because of the lesson, work, attention, environment, feelings or what not. I do know that she has ICT, Art and Self-Study lessons both of which she does not enjoy and can be quite unstructured. She can also be quite 'physical' with this teacher, shoving her in a playful way, playing with her hair, squeezing the teachers hand when she wants to hurt herself (this is part of her behaviour plan) also therapeutic 'hugs' with this teacher too. 

I try to ignore her and limit conversation, also completely changing the subject and interrupting her (to a point) when she talks non-stop about her teacher hoping it will bore her. 

I may be over reacting a bit and it could be nothing but what are your views on this? Could it just be simple or is it something more complex?