SpongeBob has many friends, but the only one who really seems to be a friend is Squidward (I think Patrick is a detractor who specializes in dragging his feet), as evidenced by the following shots.

First footage: SpongeBob and Squidward sleeping together. SpongeBob finds Squidward when SpongeBob is afraid to sleep alone. Although Squidward is very reluctant to sleep with such a little naughty boy. But after seeing SpongeBob's look of help, Squidward chose to sleep with SpongeBob. From here, we can see that Squidward is still very sincere about SpongeBob's friend, or else why would he agree to SpongeBob's uninteresting request?

The second shot: when SpongeBob and Squidward are hanging out together, Squidward is wearing the fishman's jacket that he dislikes the most. From here we can also see that although Squidward dislikes SpongeBob very much in normal times, when it comes to the critical time, whenever SpongeBob needs his help. Squidward will try to satisfy him, perhaps the friendship between friends is also like this. Mouth said very dislike, but as long as the friend a difficult, no matter anything we will go out and try to do, just our Squidward treat SpongeBob this sincere friend's way is not the same. I don't know if you are also this knife mouth and tofu heart to treat their friends?

The third shot: Squidward's kiss. From the picture above we can see a kiss on SpongeBob's head, so it seems that Squidward actually likes SpongeBob quite a bit. How else would he give him a scented kiss? Everyone treats their true friends differently, maybe I'll be as warm to you as SpongeBob, or maybe I'll be as cold to you as Squidward. But I hope those who are treated like friends please do remember that true friends don't talk about it.

Fourth shot: granting SpongeBob's wish. In one episode of SpongeBob SquarePants, Squidward is saddened to learn that SpongeBob has a "terminal illness". So Squidward found SpongeBob and said to him, "SpongeBob, do you have any wishes? I will help you to realize it. In this way, Squidward accompanied SpongeBob to play for a day and helped SpongeBob to fulfill his many wishes. Just as dusk was coming to an end, Squidward cried. Because he knew that SpongeBob, who was right next to him, had left him and he had lost his good friend. But unexpectedly, SpongeBob didn't have a "terminal illness", just a simple cold. After Octopus discovered this problem, the reality of warmly hugged SpongeBob, and then began to knife mouth tofu heart mode. Doesn't this point prove that Squidward is SpongeBob's true friend?

The fifth shot: Squidward telling jokes to SpongeBob. Inside the anime, Squidward is like a real-life adult, and SpongeBob is a little kid, a little kid who seems to know a lot about reason. In front of Squidward, SpongeBob is very eager to share his happiness, while Squidward thinks he is very childish. On the contrary, Squidward also hope to often give SpongeBob to tell the truth, make him grow up as soon as possible. Maybe true friends are like that, helping each other and making up for each other.

Sixth shot: Squidward accompanied SpongeBob to deliver pizza. From the picture above we can see that Squidward is very reluctant to accompany SpongeBob to deliver pizza. But this is just an expression to reflect the meaning, in fact, Squidward's legs are still very honest well. Even if he is not willing to deliver the pizza, but in order to accompany SpongeBob, Squidward still lifted his 4 octopus feet. True friends will never put the friendship hanging in the mouth, on the contrary, will show unusually flat, even you can not feel.