Whatever the case may be or whatever might have caused any misunderstanding between you and your partner and your partner is always to quit on you at any slight mistake or opportunity, it's glaring that, that relationship is heading for the rocks and it'd be your partner's own undoing.
Whenever there is a misunderstanding in any relationship partners are meant to talk it out, pour out their minds and feelings to each other on the situation on ground and then fashion out a solution to the situation. You can never underestimate the power of communication because communication is key in every successful relationship.
If your partner does not give room for communication and amicable resolution of conflicts in your relationship but instead always quitting on you or threaten to quit on you, i think it's high time both of you sit down to discuss and fashion a solution and if no solution is coming to fore then both of you should break up and go your separate ways because that would mean one of you ain't happy in that relationship or both of you ain't happy in the relationship.
My simple advice for you is to communicate with your partner and pour out your mind, views and opinions regarding what's causing the disagreement and try to agree on a solution, if not, just amicably agree to go your separate ways and live happily forever after.