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Me [28M] with my SO [21F] 2 years, she likes feather soft, I like concrete hard.(r/relationships)
I just want to say, in between all of the “he cheated on me” and such relationship troubles, I really love this lighthearted one!
That being said, I’m pretty sure there exist bed toppings (stuff you put on the mattress) that are in varying shades of softness or hardness. Perhaps you could find one that is hard enough for you and fits the size of half of your bed.
You could also do the opposite, get a hard mattress and have her get a foam topper for her side.