I would go by the woman's preference. If you're not sure, make it a question: "How do you do, Mrs... ?". Or ask her outright which name she prefers. Might also want to ask if she prefers Mrs or Ms.
I'd go with Ms. Alba. "Ms." has no connotation with respect to the marital status of the woman. "Mrs. Alba" would never be correct. If you use Mrs. it would be Mrs. Warren.
Yes, because Mrs. Alba would not be her name, either. "Mrs." denotes a marital status and it is attached to her husband. If she changed her name from Alba to Warren, she could use either Ms. Warren or Ms. Alba. Since she did not, she's not tying her name to her husband. So if you're calling her by a formal name, it would be Ms. Alba.
I've known several women who have kept their maiden name. They use either Miss or Ms (my sister uses Miss) + their maiden name professionally and on formal documents, but often use Mrs + husband's surname in their personal life, e.g. at their children's school. The wife of the deputy Prime Minister of Great Britain is an example. The tabloid newspapers never know how to write about her and tend to say Miriam + her long Spanish surname, avoiding the Miss/Ms/Mrs completely.
i would strongly advise against doing that, since it would anger many women, one of which may be ms alba! it may well not even be her legal name, since it's possible one can legally choose to not take the husband's surname on the marriage certificate, so why be rude and address her by a name she does not legally have and most likely does not want to be known as? on the other side of the coin, a former brother-in-law's mother once worked for greer garson, who insisted she be called 'Mrs. Fogelson'...
That would be the reason not to use "Mrs." at all. My last name is not my husband's last name, although occasionally I am called Mrs. [DH's last name.] I don't generally take offense to that, and on occasionally will refer to myself that way for clarity's sake, if we're someplace where no one knows me, but only knows my husband or one of my children. It is not, however, legally my name, and there are no documents or anything "official" that have my first name and my husband's last name together as one person. Really, it's best to just abandon the use of Mrs. and Miss and just go with Ms. if one is uncertain. Miss is okay for a child, but generally not recommended for a grown woman today. Women have reached the point where they are not defined solely by their marital status.
My wife sometimes follows her own cultural tradition of retaining her maiden name, in which case she is Ms. Chan, and sometimes follows my cultural tradition and uses my surname, in which case she's Mrs. Rowe.
Since i have a lot of military veterans in my family i would just call the woman ma'am in a very respectfully manner.
In England there is no shame attached to being unmarried, and women are perfectly happy to be referred to as "Miss". It is absolutely standard in schools, for example, to call teachers "Miss + surname". "Ms" is very rarely used, and anyway, "Miss" is no reflection on a woman's age or maturity--actually, children are not generally referred to as "Miss-so-and-so" they are just known by their first name. I find this statement extraordinary.
Just to clarify, it has nothing to do with any shame incurred with being unmarried. It has to do with the fact that a woman's identity is not completely tied up with her marital status. Here, there are teachers who are called Miss Surname, but that's pretty much the only place I hear "Miss." It's not that children are commonly referred to as Miss Whatever, but on the rare occasions when it is used, and the person referenced is not a teacher (especially a preschool teacher, where for some reason, at least some teachers are called "Miss" irrespective of whether they are married), often the speaker is referencing a child. The use of Miss is not so rare that people wouldn't know what one was talking about. Especially older people tend to use it more. But it's really an antiquated notion to base the identity (and something that is so tied up with identity, such as a name) of an adult woman based on marital status, and especially as people marry later than they had before, and with it not always being obvious whether a woman is married, the most proper title, if one has not been informed otherwise, is to use "Ms." (Unless, of course, the woman is entitled to the use of "Dr.")
Yes, but by your token if you refer to a woman as "Dr" "Major" etc you are basing her identity on her job/academic qualification. I don't see what the problem is with having your marital status part of your name, frankly. It's just a label to make identification easier, like taking your father's surname rather than your mother's. However, I live in a country where surnames are not in everyday usage--we use first name + hanim for women (married or unmarried) and first name + bey for men. But I don't want to take the thread off track.
That's fine, but the question didn't deal with Turkish society, but referenced Jessica Alba, who is a figure in contemporary United States society. The "label to make identification easier" really has to do with the name itself -- usually, in the United States, the most identifying name would be a first name followed by a last name. The "Mr." or "Ms." doesn't really differentiate, except as to provide an indication as to the gender of the person. "Dr." is an earned title, unlike "Mr." or "Ms." Therefore, people often seek to identify with that title, and see it as a show of respect for having earned it. Marital status isn't really something that one strives to "earn." And many people do greatly identify with their profession or educational credentials. If one wants to err on the side of caution, the more respectful title should be used. But, just as there are many different personalities, different people have different feelings about how important it is to them to be referenced with the title of "Dr." If a woman wants to be called "Mrs." then that's fine. But if she has not changed her name to that of her husband's, that does indicate that she does not wish to change that portion of her identity, and is not tying her name to her husband's name or to her marital status. Since she has made this particular decision, with respect to her identity, it would be presumptuous to assume that she wants to use the title "Mrs." If one knows nothing else about the woman, other than the fact that she has not changed her last name, it seems to me that it would be a more dangerous choice to call her by a title that ties her identity to her husband. Obviously, there are many women who would not be upset by this, particularly since it is such a long-standing tradition. But why do something that could cause upset, when it's so easy to just use the choice that has no tie to marital status? And yes, there is the issue of the patriarchal nature of surnames. But the issue of identity comes more from the long-standing nature of one's name than from the particular origin of the name (although that can have issues, as well.) Usually one is given a first and last name as a baby, and over time, one becomes very used to that name and identifies that name with him or herself. Since women no longer become the property of their husband upon marriage, and because by the time a woman marries today, she often has accumulated educational and professional credentials under the name she has used for her entire life, not every woman wishes to give up that identity. So, the identity value of a name has to do more with what the individual has done over her life, rather than the origin. As you pointed out, though, this is a slightly different issue than that of title, which is the subject of the OP's question. It does, however, have some overlap.