Passage
I will not leave you desolate: I come unto you.
I will not leave you desolate: I come unto you.
John 14:16 And I will pray the Father, and he shall give you another Comforter, that he may be with you for ever,
John 14:17 [even] the Spirit of truth: whom the world cannot receive; for it beholdeth him not, neither knoweth him: ye know him; for he abideth with you, and shall be in you.
John 14:18 I will not leave you desolate: I come unto you.
John 14:19 Yet a little while, and the world beholdeth me no more; but ye behold me: because I live, ye shall live also.
John 14:20 In that day ye shall know that I am in my Father, and ye in me, and I in you.
The verse centers on "leave", "desolate", and "come". It is saying that the verse draws attention to "leave" and "desolate", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 17's "even the Spirit of truth whom the..." into verse 19's "Yet a little while and the world...", so "leave" and "desolate" belong inside that flow. In John context, the local focus is the identity of Jesus, new birth, eternal life, and belief and unbelief.
A plain takeaway is to answer the verse's own emphasis on "leave" and "desolate" with trust shaped by these words, not by a vague optimism outside the passage.