I think you have a plan and should stick with it rather than start something that'll only end up discouraging you. Continue driving to work and ride there as you're doing, maybe increasing the size of the loop, or at peak supper hours doing a 2nd or longer ride after work, before it gets dark.

Maybe as you recover some of your old speed, or unload some ballast, you can revisit commuting a few times a week (there's n o rule that says either commute every day or never), or look for a longer ride that goes around the hill.

So, don't make big plans and mentally obligate yourself. Just ride when you can and if you feel like it, and as you get into the swing, maybe the mood will brighten also.