I do not know how to fix this sentence.
When couples do not communicate, they pull in different directions; making it harder to trust in current and future relationships.
There's nothing wrong with what you've written.
You've used harder, so you need to say harder than what. If you want to complete the comparison, you would add "than previously" (or something similar), but this isn't required here because it's implied.
(If you're writing something very formal then you should probably add it in - some people will still want it and it would be a shame to loose marks or annoy a superior over a difference of opinion on grammar.)
|link comment||answered Sep 29 '11 at 19:12 Siân Harris Expert|
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