Hi Quebec:
Sounds like you have a plan going for you!
From what you wrote, I would say getting going in a volunteer capacity would be a great way to go. There's no great hurry with any of this. Ultimately, you may find that you're just better off being a volunteer than trying to get back into paid employment. Volunteers provide vital services. One can be very proud of the work they do as a volunteer!
Besides getting yourself back onto a schedule, & out into the world, the other thing that volunteer work can do for you is to demonstrate that you can perform in a work-type setting, it gives you something to write on a resume or job application. It also can provide you with some potential references. So there are lots of side benefits to being a volunteer. And there are a wide variety of volunteer opportunities typically available. Here in the Twin Cities, where I live, there is a service that helps people seeking volunteer positions find positions that are of interest to them. You might check to see if there is such a service available in Quebec.
The important thing is: don't dive in too quickly. Be good to yourself. Begin at, perhaps, 10 or 12 hours per week. Then build up gradually from there. You may want to try out a few different things to see how you like them. You can also either, eventually, do several part-time volunteer jobs, or you can devote all of your available hours to one in particular. Good luck!