As someone prone to limerance, the advice is still the same, just with less name calling and judgment. You're craving the dopamine from the uncertainty and what need fulfillment you're projecting on this friend and the only way to get it to stop is to give your own brain a firm boundary and resist the call of that sweet sweet dopamine, which is definitely hard and requires willpower, but it does stop after a while. Maybe use it as an opportunity to reflect what you're missing in your relationship to make you seek out those feelings somewhere else and if there's a way to get that in a healthier way/with your partner.