It seems you have three options; ask for more time being monogamous(with another end date), date with him (which quite frankly will give you time because very rarely works for couples to find dates), or decide to be okay with him dating other women. Maybe one more; date guys while he dates women. Which one is the one that feels most comfortable is where to start I think. Ask for that first.
If he blows up, he blows up. That's a valid emotional response, but not helpful to sorting it out. Figuring out what option is next is the next step and so on. Until you have a mutually agreed upon boundary. Or, you might just find that you have to discuss who is going to be most damaged in a comproimse and one of you decide to be considerate enough to suck it up and compromise so the other can have more freedom. I did this with Mono for a number of years (I didn't date any other men) and am now finding that the time paid off, because there has been a shift and he trusts "us" more than when we started out on this road. Some things just take time... Like years!
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