Heya @the-janelane, I am so glad you have started this conversation. Like most diagnosis everything works on a spectrum, so yes absolutely many people with BPD would relate to the infactuation you speak of. I have heard some refer to it as "obsessive attachment" but in essense it's that same feeling of idealising one person for a huge portion of the day.
It's interesting to note the feeling in your body, the memories that are activated and what element of you is coming forth when this person comes into view for you. I am keen to hear the rest of the communities view on this, and please know you are not alone You also have an immense amount of self awareness which no doubt will aid you in the healing journey.
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