If this chap is a good friend, then surley a bit of negotiation would resolve it? I would have though a new 172 could do the 100 mile in an hour, so one hour for you to drop it off to him, with the condition he drops you at the station to get home. Then he brings it back 2 weeks later and you drop him to the station and catch up on things with him, seeing as you wont be seeing that much of him while he is going through the honeymoon period with his new bit of skirt
Trust me, he will be back into the pilot seat soon, like less than six months the novelty of the new woman will be wearing thin. Stick with it for a month or so and see where it goes to! Dont burn bridges in haste, thats my two pennorth for what its worth.
PB