reason for divorce change?

Is it possible to have a reason for divorce changed, even if was over
20 years ago?
You are probably thinking why bother?
Well, my ex divorced me on the grounds that I was jealous and I behaved
in a way which she cannot reasonably be expected to live with me.
Evidence has since come to light that she was indeed having an affair
with my best friend and eventually went on to marry him, I also have
evidence of her having an affair with another man in the form of
letters sent to him (dated and signed)
I am not a jealous man, I suspected something was going on at the time
and when confronted with my suspicions, she went for the divorce
option.
I returned to my home town (400 miles away) and was unable to defend
myself in the divorce court.
I just wish to clear myself (so to speak).
On another point - the divorce papers clearly stated that she has no
objections to reasonable access to my children yet a further letter
from her solicitor states that I would not be allowed to contact the
children in any way, I have not seen or spoken to my children for over
ten years now, with the exception of a recent two-day visit from my
son. My ex has returned birthday cards, moved properties, changed phone
No's, and even told the kids I was dead! so could not have contact. I
could'nt send child support as I did'nt know where to send it, nor did
she ever ask for it.
Now my son has made contact, she has now applied to the CSA for money
and a DEO will be enforced next month, for my daughter who is now 18.
I would like the divorce reason to be changed and possibly some action
taken against either her or her solicitors for not allowing me to have
contact with my children all these years, something which can never be
replaced.
Any comments/replies welcome.
Now my son has found me (thanks to the internet)

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