You should definitely do things your own way, and I get that you want to “enjoy your experience,” but I’m not sure what experience you are expecting to have at this point. Keep in mind that this is a business and the way the SAs make money is by selling products across the range in the store. That is how they earn a living. If you’re not buying much, she isn’t making any money. That is her “experience” with you. It’s not a problem to go in and buy one scarf, and the next visit buy a perfume—that’s completely fine, but just adjust your expectations of her accordingly.
It sounds like you actually have a good SA who is bearing up pretty well under (by your own admission) frustrating circumstances. If you want to improve your relationship with her, then unless your purchases are reasonably substantial on your purchase visits, I would keep your non-purchase “just looking and saying hi” visits to a minimum. If you only buy a perfume or a Calvi on your purchase visits, then you really need to eliminate non-purchase visits altogether right now. When you start to build a strong sales history, you can do more idle browsing, but until then, from her perspective, she’s having to work too hard for minimal reward.
While likely any SA will keep you as a client and get you what you want, with your current pattern I doubt you’ll ever get that warm, fuzzy, super-attentive feeling that you might be hoping for. A “long-term and meaningful relationship” as you have told her you want to have, is only “meaningful” for her if you actually buy things. There is no point in switching to another SA in the store because they all talk to each other, so all the SAs will know your spending/shopping pattern. It’s good that you are not expecting a quota bag offer.
What I’m guessing when you went in to exchange the Calvi and wanted to look at the Picotin is that she had another appointment and knew that you were not really interested anyway and didn’t want to take 20 minutes to go through the rigamarole of showing it to you if you were not going to buy it. If you are serious about buying a Picotin, then put it on your list before your next appointment with her and when she shows it to you, buy it.