Just to give my two cents:
While I do prefer Aki over the husband, she's still married so I wouldn't push this relationship over the point of no return just yet. Yes it's annoying to get cucked every single chapter, but going thru the husband perspective, if your wife cheated on you, you'd prolly be angry also. So in order for this AkixSensei relationship to progress, sensei has to be the one to break off from her husband realizing its a bad marriage.