I would like to chime in here and post something.
I do not believe that Jesus was condemning her at all. In fact, I believe He was just 'testing' her to see what her heart was like.
Someone can correct me if I am wrong, but in that day and age a woman did not divorce a man. He was the one that always did the divorcing. So for 5 men she had been used and then abandoned. But yet her heart obviously was drawn to another man; just as God had ordained it from the beginning. If anything she was pure in her motives. Which is indicative of her not lying to Jesus.
And there is no indication, when look at the original language, that she was 'living' with or having an intimate relationship with this man. Here are a few different translations.
KJV
For thou hast had five husbands; and he whom thou now hast is not thy husband: in that saidst thou truly.
ESV
for you have had five husbands, and the one you now have is not your husband. What you have said is true.
YNG
for five husbands thou hast had, and, now, he whom thou hast is not thy husband; this hast thou said truly.
This is where looking over multiple translations comes into play. And even the original language is not a bad idea to study either. What happened is some translators, who translate paraphrase style, have deduced by their own reasoning that Jesus was stating this woman was living with this man.
But the fact is the original language does not state that, and when translated word for word, not thought for though, we can dive a little deeper into what Jesus was stating.
"hast" and "have" is the Greek word echō
1) to have, i.e. to hold
a) to have (hold) in the hand, in the sense of wearing, to have (hold) possession of the mind (refers to alarm, agitating emotions, etc.), to hold fast keep, to have or comprise or involve, to regard or consider or hold as
2) to have i.e. own, possess
a) external things such as pertain to property or riches or furniture or utensils or goods or food etc.
b) used of those joined to any one by the bonds of natural blood or marriage or friendship or duty or law etc, of attendance or companionship
3) to hold one's self or find one's self so and so, to be in such or such a condition
4) to hold one's self to a thing, to lay hold of a thing, to adhere or cling to
a) to be closely joined to a person or a thing
Quite literally its the idea of when the person marrying a couple states "to have and to hold forevermore". This woman at the well had five different men she had given her heart too, and yet once again she had done it again. If anything, there seems to me a tone of sadness when she answers Jesus. As if she was depressed that all these men had left her and she now bore the shame of having been divorced 5 times.
We never see Jesus state that she sinned, and never hear a word of rebuke. So we cannot say that He in the least condemned her. Some compare this to the woman caught in adultery, which interpreted the way most do would also say this woman was committing adultery also. But there is one thing that stands out with the other story. Which we would be wise to take into consideration when doing study like this.
Jhn 8:10-11 Jesus stood up and said to her, "Woman, where are they? Has no one condemned you?" She said, "No one, Lord." And Jesus said, "Neither do I condemn you; go, and from now on sin no more."
So in my estimation, this woman is not living in sin, yet she is heart broken, and Jesus is there to mend her heart. That is why "He must go" to the well.