Hi Fussy, Welcome along, stick with me and you'll be fine!!
If I may be so personal and ask "Is She A Townie"? If she is, just walk away while you still can. A friend of mine got involved with one of those a while back, and it wasn't pleasant.
If she's one of us and once a more up to date model well theres hope, counseling is always an option (for you her or both). And your well on the way down that road by joining us. This is just counseling without the bills. Maybe you should look at the broader picture, surely she has her plus points? Or maybe not? I suppose changing the tractor to one in her favorite colour wouldn't be an option? Theres always the wheelbarrow, now its not difficult to drive, and easy to paint.