I often see this phrase and I'm never too sure about the specific range of interpretations. In particular the literal translation would be “may ..., but ...” but I feel this is an idiom in English that is mostly used in cases that don't indicate possibility but certainty and indicate a sense of “regardless” and I feel something such as “友人だろうとそういう行動を許さない” would sooner serve as a translation of “You may be my friend, but I won't tolerate such conduct.”. As in, it's considered a certainty in this situation that someone is the speaker's friend regardless of the use of “may”. Every time I encounter “〜かもしれないけど” however I try to analyse the context to see whether it expresses a certainty or a possibility and up till now I never once encountered a context where it could be a certainty, leading me to tentatively conclude up till now that “〜かもしれないけど” cannot be used similarly to “may ... but ...” and that “友達かもしれないけど、そういう行動を許さない。” thus always means “It's possible that you are my friend, but I won't tolerate such conduct.”
But, watching The Demon Prince of 百千 House right now, I may have found my first counter example, the protagonist at one point says “ここは、私の家かもしれないけど、居場所じゃないんだ。” while it legally is the protagonist's house, though there are some disputes over the ownership of the house regardless so it's not entirely certain.
So can “〜かもしれないけど” also be used in cases of certainty and is “This place may be my house, but it's not where I belong.” a suitable translation which in English does not raise the possibility that “this place” is not the speaker's house, or must the translation be something like “It's possible that this place is my house, but it's not where I belong.” and does the Japanese sentence still unambiguously acknowledge that the statement of it being the protagonist's house may or may not be true?