We all have those days! Congrats to you to realizing what your triggers are, and what behavior you want to change. That is half the battle right there! Kinda stinks to see it happening and know you are going to go down that same road again even though you know it never works, right? Yes, been there, done that. But you are strong and smart and you will get through this.
I think what you need today is to know that everything you do and have is a choice. You can choose your mental attitude regarding the bf; you can choose whether you put food in your mouth to cope with it; you can choose to do something really good for yourself. You can make absolutely any choice at all...but you are the one who deals with the consequence of the choice...good or bad. You can't make choices for your bf, but you can take care of yourself when you are dealing with him and it's not going so well. If he doesn't like your choice, that's his issue.
Ask yourself if you really want to waste the rest of the day's emotional energy on this. Stuff like this can hold you hostage and then boom, you lost a day that could have been better spent. Sometimes you need to give yourself permission to feel bad for a little while to get it out of your system and move on.
At the end of the day, you are the one looking out for you. And you deserve something good.