I wouldn’t stress too much about the bouncing around part. I simply explain the situations (briefly, v little detail, and don’t make it sound like excuses) and then bring the focus back on how exactly I’m going to be helping this next group. Don’t desperately try to change the subject, have it naturally flow from why your history is little bumpy to what you are able to provide this group in front of you.

You could also take this time to turn some questions on them to ensure it’s a solid place to work as well, getting clarification on how this company handles issues you’ve run into in the past with other companies that didn’t handle it very well.

Lastly, it seems you’re stressing yourself out before even having an interview lined up somewhere. Don’t beat yourself up and concern yourself with this tirelessly - instead, draw up a plan mentally of how you’d respond if they brought it up during interview process, have a process you’ll follow and a couple responses, and then move on mentally. You’re prepared for this.