Calling it Quits

After 8 years of going out (with a 7 month break up) and an initiation of a continued relationship by a way of engagement by my then boyfriend (which has lasted a year an a half) I told him I didn't want to get married, my heart isn't all in, and I have had reservations, he still wants to work it out by going to counseling and agreeing on exclusivity. He says a person doesn't have to be IN LOVE they just have to be there and be committed, plus He says I am not getting younger. He is not mad at me for expressing my emotions and but he says he would be pissed if there was someone else, whether it was girl or guy. I told him no, because this other person has rejected my profession of strong liking (emotional cheating), I have not had sex with them, and did not ask to be involved. My SO is also a homophobe. I am not sure what I should. Tell him about this other person? Say I actually want to break up (which I feel like I will sorta regret, or go to counseling and date non-exclusively? I feel like if we agree on the latter, he will strongly belive that there is someone else, which is not the reason I wanted to call it quits.