Be they opposite-sex or same-sex, couples get themselves into hot water all the time because they forget simple truths, things that work.
One thing I often notice is that people get a highly detailed and particular idea of what love should look like --in their less than humble opinion--and then fail to notice the love that is being given to them, only because it comes in a package of a different color.
The anniversary game is all too typical. Ditto for Valentine's Day.
And for people who are not in the mood for sex at the moment, almost always say "yes" and you'll be surprised at how often that gets you in the mood after a few minutes.
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