How to justify your TOM to your significant other! (Q49137)

We have all been there! How do you explain a several thousand dollars investment into another "toy"? My significant other (SO) had some issues with the amount of money and specially time I spent with the TOM. Not even http://www.thingiverse.com/derivative:9461 won her over (though it did get some extra time credit over all). I needed something significant ( in monetary terms ) to bring her over to our side. In my case, I had the (mis)fortune of breaking the end of my cars luggage compartment cover. The cover can be used in the 5 and 7 seat configuration so it has extensions that lock to the ends to make it longer for the 5 seat set up. The broken piece that connected to the left extension was around a bit and I tried the usual super glue cure with terrible results - not only it did not glue properly, it actually made me loose the broken piece altogether (now I see it was divine providence!). Upon contacting the dealer to try to buy the offending plastic part and after being politely told to stop being foolish and that Plan B (a whole new cover) was going to cost USD 550, I saw the light! :0 What if I fixed the cover and saved USD 550 (plus tax)? Hero for a few days maybe and even, just maybe a "isn't nice that you bought the 3d printer thingy?" Lofty goals but the difference between courage and ignorance is usually not that big.