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My personal experience suggests that any hope the couple may have of eventual success together depends on them first getting the open flame away from the gasoline, that is, not being in physical proximity to each other. Coincidentally, that's also their best chance for dealing with their individual issues. It will probably lead to a break-up, sure, but the current conditions make not only a break-up but worse complications inevitable.
So yeah, even if the LW really, really wants to salvage things, he still needs to get out.