The emotional investment in this relationship doesn't seem to match the actual dynamics of it to me... something is out of kilter. IIRC from the moved thread, she hadn't even been in your room when she first laid eyes of Whiplash. So I'm going to take it that you aren't close to the next level of living together, or engagement/marriage..
Nobody in a 'dating' situation should have that much emotional, and certainly financial control over the other party.. My partner and I of 10 years only went as far as having a joint bank account 3 years ago, and that was purely because of payouts arising from our big earthquakes in 2011.. To this day we only use that account for grocery and bill expenses.
I may joke about her disapproving tone when I start sounding too impulsive about Hot Toy purchases. But she does make valid points about lack of space to display them, and the fact that we want to buy a house together. (She already owns her own place rented to her son). Ultimately though, at the end of the day, she doesn't have to approve any of my personal expenditure, especially as the house we currently live in is provided by my employer, rent and power free..