You are misusing the expression "beneficial to". You can use "beneficial" with a prepositional phrase, "exercise is beneficial to the heart". Or you can use a cleft sentence to say, "it is beneficial (to the heart) to do exercises". But you are attempting to say that something doesn't help alleviate a problem, and this isn't what "beneficial to alleviate" means.
But there is no need. The word "alleviate" already means "get better" (or get less bad) so it already has the sense of "benefit". So it would be good just to cut out the awkward use of "beneficial" or "benefit" and say
The quarrel you both have Your quarrel won't alleviate the problem.
I've tightened up the start of the sentence. You can also say "won't help alleviate..." to add nuance or change "alleviate" to "solve" for a slightly stronger sentence.