Relationships with fools: Interpreting the Dhammapada Dhammapada Verse 61: If a person seeking a companion cannot find one who is better than or equal to him, let him resolutely go on alone; there can be no companionship with a fool.    

This is obviously self preserving pragmatism of the Aesop's Fables variety, it doesn't require a Buddha to say this, so perhaps there is a deeper meaning I don't spot. 

Besides, I spot a couple of problems. 

One: For me to associate with someone better, that person would have to accept me, his/her inferior. Ergo, one of us must break this rule and accept an inferior (not necessarily a fool) as partner or companion.

Two: This doesn't sound very loving and compassionate. Fools will remain fools without the company of intelligent partners or teachers, is it not? Plus, the Buddha himself tolerated Devadutta and others who were often comically stupid in his order.

The accompanying story of the Thera who blindly trusts his disciples is a little too simplistic, how is it that a senior teacher (Thera) needed to be schooled on such a trivial principle of common sense?

If someone is obviously lazy and scheming, even treacherous, he or she should not be trusted. Did the Thera get undermined by a false sense of duty or compassion?
The verse speaks from the point of view of the bhikku. The verse should be understood properly:

The bad and good bhikkhus were searching for companionship.

They found companionship with Thera.

The bad bhikkhu did not respect Thera, was not obedient and dutiful and was offended and extremely angry when Thera said something to him. Why? Because he thought that Thera was not better or equal to him. Thus, the bad bhikkhu choose a wrong companion. He should have let Thera go on alone and find a companion who is equal or better than him. There can be no companionship with a fool.

The good bhikku was respectful, obedient and dutiful. Why? Because he thought that Thera was equal or better than him. Thus, the good bhikku choose the right companion. He was not in a companionship with a fool.


  One: For me to associate with someone better, that person would have to accept me, his/her inferior. Ergo, one of us must break this rule and accept an inferior (not necessarily a fool) as partner or companion.


This rule can apply and not be broken. If a man and a woman are seeking a relationship and they both think about each other as being equal or superior to the other, the relationship/companionship will work. Otherwise it will not work, as one will think about the other being a fool, or both will think about each other being a fool.

If a bhikku is seeking a companionship with a teacher and the bhikku thinks about the teacher being equal or superior to him, the companionship will work. Otherwise it will not work, as the bhikku will think about the teacher being a fool.


  Two: This doesn't sound very loving and compassionate. Fools will remain fools without the company of intelligent partners or teachers, is it not? Plus, the Buddha himself tolerated Devadutta and others who were often comically stupid in his order.


The verse speaks from the point of view of the bhikku, not from the point of view of Thera/teacher. 

If we were to apply this verse as you’re suggesting, then the Buddha would never have taught the Dhamma to people obviously inferior to him, or less developed than him. 
Or if we were to apply this verse as you’re suggesting, then the Buddha is contradicting himself. But he is not, which can be clearly seen by his actions - he thought the Dhamma, even to fools.