What about doing one or two rides a week with him and then a few on your own? I think it's good to ride with your spouse and he might need the motivation, especially if he's new to the sport, but it's also good for you to get a good ride in. Are there group rides that go out and maybe split up by skill level so he can do the easier one, you do the harder one? Hate to say it, but if he's new and you don't ride with him, he probably won't ride. When I first started mountain riding, there is no way I would have gone out without my husband. Although it's for different reason (didn't know basic repairs, lost on trails, etc) but he might have his excuses too (not confident crossing roads, riding in shoulders, basic repairs) until he has more experience.