haha... i've always wanna believe in the good wills of all human
being...
I wish sometime, affair can be as simple as an act of stealing.
Ppl tend to blame it on love being blind, etc and somehow get
involved with married man. Which might b the case for TS. Which is
why i am curious as to what goes on in their mind that somehow
propell them down a hopeless route which they all know to
avoid. then again, am sure there is load of cases where the
ger is all out to get that man she want, be it married, 80yrs old
or wat.
I agree with u on the envy part. Why build another family hubby
out of a man when u can have them pre-builded and tested. with the
slight stain of fidelity.... but hey if i can get him to leave
his wife, hell am sure can keep him by my side
always.... 
Well Earl, like most human beings, some women can be selfish,
competitive and what propels a woman to continue this "hopeless"
path , is hope itself.
Women who are prone to affairs with married men usually wants to
prove that she is BETTER than the wife. The competitive streak.
And because she HOPES to get that juicy steak on her plate ,
instead of someone else's , she continues with the affair, hoping
for the tide to turn in her favor. Much like a gambler who refuses
to give up.
Frankly, I don't know of any ex-mistress turned wife who is
happy for long , with the man she managed to steal. Not many
mistress will admit publicly she bagged a garbage.
As the saying goes. "The best revenge is to let the other woman
have him."