For husbands or SOs of endo sufferers, God bless you. I mean it, I'm not being tongue-in-cheek here. It's challenging to lovingly handle a wife who is almost constantly in pain. My own husband is amazing. So for all of those other husbands out there, let me give you a few tips:
The pain can come in a matter of seconds, so if her mood changes, don't hold it against her. When I hurt, I'm ill. I am a flawed person and this may be one of my biggest flaws. Sometimes as soon as a snappy word comes out of my mouth I'm apologizing, and sometimes not. But he understands, and he never criticizes my criticism.
If she didn't feel like it last night, don't be mad if she doesn't feel like it again tonight. Sometimes those moments without pain are brief, and trust me- she'll let you know when it happens. And in the mean time, sitting in a hot bath can help alleviate the pain, so why not draw up a smelly-good bubble bath?
If you married/dated an independent woman, that independence may waiver at times now. I pride myself on my work ethic and ability to work alongside men without faltering. Or at least I used to. Now I can't lift a case of water without feeling those familiar muscle groups tighten all at once. Be aware that she might need more of your help now, even if she's too prideful to ask.
I'm sure there are more. If you could be a fly on our living room wall I would just tell you to do as my husband. He truly is wonderful, and understanding. He never gets impatient when my pain keeps us from doing fun things we already had planned, and now he can pretty much tell by the look on my face if I don't feel good.
But remember- it's not her fault that she has a disease with no cure. Love her anyway, and she'll love you even more for it.