No, it is not wrong to need someone but we can't depend on someone else to give us happiness, comfort and peace. I think people need the companionship and love of someone, a partner, family. I think our society has definitions of family, of couples, and singles just don't fit anywhere.
I think that when a decades long parthership is broken by death, the survivor is no longer part of "us" but is just "me" and that leaves a big gap in our lives.
I know a woman who hasn't changed a thing in her life; her husband's clothes, glasses, everything's still where he left it, as if he's just stepped out and will be back any time. It's spooky. I know a guy who gave away everything; no evidence of his wife's presence in his house or life. He doesn't even talk about her. I'm somewhere in between.
and I about had a heart attack a few months ago when my brother-in-law (who I hadn't seen in years because he lives far away) came to visit. I met him in a restaurant and he was standing by the bar when I walked in. I saw him from behind and he looks exactly like his brother, my late husband. I almost stopped breathing. Same bald spot, same neck, same body shape, same forhead. His voice is different & the way of talking & he's much more bitter and more of a drinker. Still, it was an awful shock.
I wouldn't look to find someone else to make me happy but I would look to find someone who could give me joy and satisfaction and comfort - and love and respect. It's a tall order