If he is really trying to do the right thing, he would be working with you to get the garage repaired and be more transparent w/you. If he was really trying, he wouldn't be doing the things he's been doing w/the ow. You are not second best, you are the prize and deserve to be treated w/respect and love and his honesty about what he's doing.
Stay the course. When in doubt, do nothing.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.