Hi Juditha,
I think you may be missing the point, but then I do have a complete run of Star Trek TNG videos to fall back on!
As any trekkie will tell you, for any decision there are an infinite number of outcomes. You decide to go a different route to work one day, you meet someone new, he/she offers you a job/ introduces you to a bunch of new folks you might never have met, and your career/life path takes a totally new direction. Now at a quantum level, part of you went the usual way to work, you didn't meet that person, so another bunch of experiences turn up instead -and so on, every week.
If there are an infinite number of worlds coexisting together (and remember that the universe is not only stranger than we think but stranger than we can ever imagine) then in another world you might be an artist, politician, spiritual leader, hitman, hobo or anything else.
I like to think that in an alternative universe I maybe still with my first wife and we get along fine instead of hating each other as we ended up doing. In another universe I would never have met her at all and married someone else. All things are possible and indeed, probable.
As I see it in alternative worlds we DON'T live the same life because we make different decisions. Here my decisions might run A+B+C+D, in another world they might run A+B+Z+Q and so on. The sum of experiences we end up with and the end of those incarnations would all be different and all add to the sum of our experiences.
It's the free will that makes the difference (sometimes it's a double edged sword) but there's always a plan B.... or a plan C.
For instance.....2 years ago I rang up one of my closest friends to wish here happy Christmas and asked how she was. 'Fine, but the orchestra I play in can't find a new conductor.' So I applied for the gig, got it, and have meet a whole bunch of great new friends and am having a wonderful time making music with them -and it all stems from that one phone call. If I hadn't made it, who knows what might not have happened?
Hope you understand.
Live long and prosper (as they say)
David.