What about joining yourself? This is a good month 'cos there's an extra project kit that you get for free. Join under her and she'd get the kit too. That way you wouldn't be dependant on her to place your orders.
You could also use more than one demo. You could still order occasionally from your friend, when she gets in touch with you ... and have another demo that you order from.
Take the initiative. Don't wait for her to call you. As soon as you know of a special, or have an order, let her know.
Ultimately, you need to decide how important your friendship is. If she is your best friend, do you want to potentially toss a friendship over stamping supplies?
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