Ask her if she wants same. If she also agrees then you can ask her to file for divorce.
Ask few questions to yourself before though--- Are you ready to take care of her kids too. If yes, then only go for it otherwise her kids will their mother which is sad.
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It may be possible for somebody bt i think it is not good bcoz agar sirf apki taraf se ye ek tarfa pyar h to apko bhut dard hoga , bt if she loves his husband tb to ap galat kar rhe ho becoz they both are love eachother and do dilon ko dur karna is duniya me sabse bda zurm h , apne ek galati kar di yeh nhi btaya ki she loves u are not , u know what pyar sirf lena nhi janta h . if u love her alote and she dosen't loves with u, then true love is said do sacrifies . sachcha pyar wo hota h , jo sirf dena janta h , mr. bob pyar ,tyag or samarpan mangta h , isme bhut dard hota lekin ap ek paap karne se bach jaoge or dusri bat abhi shayad apko yeh samjh me na aaye bt if u understand it then ur life is good any body didn't fotgot their love bt jisme apke pyar ki khushi ho wo kijiye . taki bad me apk dil pr koi bojh na rahe ki apne koi galat kam nhi kiya h.or pyar me to sirf dard hi milta h.pyar sirf dena janta h or iska sabse pehli shart hi samarpan or tyag hoti h. bt all the best for ur li