If you go to heaven, your husband will still "own" you till he comes to heaven too (though there could be timing difference,:-)).
So theoretically and traditionally or conservatively, he might not be "ethical" if he "marry" another woman after you leave him just "a while". Remember that Chinese Woman used to be requested (madatorily by LAW) not to marry or have "relationship" with another man after her husband "leaves" her, till she "meet" him again. Otherwise, she could be thrown into river with huge stone so she could "see" him immediately... ^O^
Equally, as a modern woman living in North American, believing that "everyone is created equal", we have the right and our husband has the "obiligation" to follow the same "RULE" that they want us to follow... !!!
Therefore, if one of you couple leaves earlier, the other one might be better to follow the "marriage contract" that you agreed together at the time you say "I will...".
Similarly, if you would like to have more than one "relationship" in/before/after your marriage, the best way is to have him to "do" it first. Then we are both "ethical" and "equal" and good "executives"...
For your information only...
BTW, if your husband is much more "POWERFUL" or "richer" than you, consider if you want to keep your "bowl" before asking for the "equlity". Will he shoot you if he shares you with someone else? or if he lose you? :-) Don't worry, god is in the heaven to wait for us anytime, so we are never fearful or "lonely", ^O^