In need of some help—

My boyfriend and I have been together for almost two years. I love him to death and we had our entire future planned out together. I’m his first serious girlfriend in a long time, and for a while everything was going amazing.

Lately, he has changed into a person that I can’t see myself marrying someday or starting a family with. In fact, our relationship has turned quite toxic. A lot of arguing and lack of communication (at least civil communication) has put a really big dent in us. We’ve tried so hard to work on this for quite a few months now and it’s only gotten worse. I don’t want to break up with him but I’m not sure if I have any other choice. If I shouldn’t break up with him, what should I do? If I SHOULD break up with him, how would I go about doing so?