Is this "welcome and love to you!" Or is it the sense in Yorkshire speak where we address women and sometimes men too as "love" eg as in "Thanks love!" Even to a stranger?
The latter. It's a term of affection.
There appear to be two words for a person one is calling "love". How does one know when to use which?
If you look at Gaelic songs you will find there are about 100 words for the person you love. They will vary from words you can use for any friend to ones which are much more specific.