Life-long is too big and too far. Most probably in your age, an affair will last 2-3 years. So think about short-term future and if you survive this, good for you both and if you don't survive, move on !!
In any relationship, there will be phase when you both will discover things that you hate about each other . If you can pass that stage and accept the person with his/ her faults , love finds its way.
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