Too jerky, ride too uncomfortable, too loud.

I think you might be able to improve on the jerkiness with some 'heroic' efforts on your part when you drive BUT the ride and noise levels are what they are. Nothing you can do about those 2 factors.

So, if you will permit me to comment on your situation, IMO, you have a few choices.

1) Take her out for numerous drives to show her why the car is the way it is. But, if you do that, you would simply be going through hoops to get her approval. I think her issues are unlikely to be solved this way AND they will involve needless 'stooping' by you.

2) You resolve not to drive in the GT3 with her as a passenger. This is a sad course of action to take. Ideally you want to share her company AND the pleasure of the car BUT this choice won't permit that.

3) Sell the GT3 but you will regret having your hand forced like this and you may spend the rest of your time together subject to her dictates.

4) Break up: over a car?? I don't think so.

None of your choices is easy. I would do 2.

I think you need to take a step back and think of how you are currently interracting. It seems to me that you need to find ways to encourage her to respect a little more what is important to you and how you feel about those things. If she's used to being the centre of attention then both you and what is important to you might be getting pushed to the sidelines here.

Solution: don't lavish too much attention or importance. It's the oxygen women need to rule over you.

Hope it all works out. My thoughts are with you. If you want to PM me, don't hesitate.