You think it's ok to enable and accept drunk driving? Sami is a shit person. Anyone with sense wouldn't tolerate being in such a shitty relationship. Sami is obviously being abused and coerced. If Sami and OP have talked about this and she's insisting on staying in the relationship then it's better to be as far away from Sami and Toms "relationship" (if you can call it that) as possible. Relationships like theirs destroy all of the people around them and are a black hole of misery.

Tom's obviously the shittiest person in this scenario but Sami needs to get the fuck out and move on with her life. Tom's made his bed and not only can he lie in it he's asking everyone around him to reframe what to accept so that his actions are tolerated. It was never an open relationship it was always cheating.

If he keeps being enabled his actions are going to get worse if they haven't already.