What will you do if your partner have problem with you using facebook so much while you are not even cheating or anything

I would give my Husband my password and encourage him to check out what I was doing. Then I would try to spend less time online and more time paying attention to him. Your partner is crying out for your attention and is insecure.

if my partner said that to me i'd tell them to go fuck themselves.

Actually my ex got annoyed if i was replying to a friend on my phone he wud say he knows nobody who spends that much time on their phone - even if i was just sending one text then put my phone away - my ex wanted control & got annoyed if i stood up to him - there is a reason for him being my ex