。
Old people need someone to talk to.
Literal
Old-people [for-には] conversation-partner [subject-が] necessary [copula-だ].
には combines に (for) with は (topic): 'as for old people, a conversation partner is needed.' 話し相手 ('conversation partner') is a compound: 話し (talking) + 相手 (partner). 必要だ expresses necessity directly. A poignant observation about loneliness in old age.