Same here My friend and me literally spent nights with racing the xfg door-to-door when he was still a demo user.
You might consider buying a gamepad, wont take much space and you´ll have 2 analogue sticks to use, however you will have to convince your wife again.
Besides that, a decent gamepad will cost you as much as a Logitech Driving Force Pro wheel, assuming that you live in Switzerland and could order you Dfp in Germany for 34,50 Eur.
I´d suggest setting this to ~80%, you can still increase ffb ingame (even finer then), but without getting this "shaking" and hitting left-right-left-right of the wheel.
I had this problem and solved it with decrasing overall effects strength, which was 101%.
Just a quick hint