I saw my lover

One's lover is someone one has made love to. That's not necessarily the case with a boyfriend/girlfriend, it could be early days.

When people who are not married to each other have sexual intercourse for the first time they are often said to have "become lovers". I don't think we would say this about an encounter between a prostitute and client, or strangers having a one-night stand. Also, it would be more appropriate to adults than teenagers.

Context is important, too. In poetry, up to and during the 20th century, lover was used without reference to sexual activities. A good example of this is "The Great Lover" by Rupert Brooke. I also suggest to you that you don't know enough about English to be telling native speakers what distinctions can be made between the American language and that used in other English-speaking countries. In terms of the use of lover without sexual connotation, see "Annabel Lee" by Edgar Allen Poe. At last report, he was a native-born American.

Thank you~

Yes.

Additionally, the previous posts are wise and informative.

Shopgirls, waitresses and others in the West County (Devon, Cornwall, Somerset) are apt to address perfect strangers as "lover", if they are in a good and friendly mood.

This should not be misconstrued.

Women in the U.S. will sarcastically refer to a male con-artist as "lover boy."

Thank you~