When a relationship comes to an end in most cases it means
that at some point each of you went different pathways and as time went
by difference between you both was increasing even if all seemed to be
just fine from your point of view. It doesn't even matter what caused
actual divorce because reasons why your wife actually left you can be
found earlier in your and to get your ex wife back you need to
understand what were those reasons.
One of main reasons usually is loosing respect for loved
one and depending on emotional background it affects your marriage more
or less in separating you from each other. Since you are the one who
was dumped it means your wife lost respect for you possibly on several
occasions which built up over time and ended with where you are now.
Usually women loose respect of their men when they don't act as
stronger party in relationship unless that's what they are looking for
in a men.
Basically if men don't have backbone and can't stand up for
their self then majority of women won't have any respect for such men.
If this is the case then your mission to get your ex wife back is
almost impossible and only way to achieve it would be analyzing what
behaviour exactly made you in her eyes less respectful and working to
improve on these characteristics which not many can manage.
Next possible reason could be that either you or your wife
wasn't satisfied with lack of passion and intimacy in your relationship
which could bring either of you to seeking some adventures outside and
if other party finds out about this then it's usually sure end for any
marriage. Possible solution for this would be remembering what brought
you together in the first place and trying that out to bring back
positive memories but some improvisation is required as well.
Possible reasons are numerous and individual to each case
but with some professional help this can be analyzed and fixed so you
can have your second chance with her. What I recommend is a book
called "Win Back Love" which will help you in finding actual reasons why
your wife left you and learn ways how you could fix these problems.