“i don't know how much longer i can keep going without a friend. i used to be able to do it very easily, but that was before i knew what having a friend was like.” can anyone explain this

It is saying that he was a loner and never had any really friends. Therefore he never knew what a friend was like. Then, he got a friend that was a true friend. The friend then disappeared for whatever reason. Now, he misses having a friend. He wants friendship in his life

The quote means it's someone else saying like some one is saying that it's difficulte to get a friend.That's my best shot.