You may or may not get him to be brutally honest as to what sistuation led him to the thoughts that he doesn't love you anymore.
This could be something really silly & small.
He could have looked at another girl & thought *damn I want me a piece of that*, he may of not thought this in the two years beforehand and him thinking about this could have led him down the road of "Do I love jen12mcc anymore?".
Ask him why he wants to break up, what can't he get in this relationship that he could get in another, what hes going to do in the future. Give him a chance to be completely honest with you & promise him no repercussions, & prepare for the worst (ARE YOU prepared for him to say "well I've been seeing another girl & I really like her, I want to move in with her & make babies with her").
He probably won't say that but be prepared for the worst. When he has given you the honest answer say nothing about it, agree with him, encourage him, and then propose a solution that will fix his problem while still being in a relationship with you. (eg if he wants to "play the field" you offer him threesomes, if he just feels like he never should have said he didn't love you and he feels he didn't think it through & he doesn't know, let him save face & say, "you don't have to love me, if your not sure if you do, we can still live together and raise a child, & then when we are sure we can do something" If you LET him save face & LET him still live with you it'll become easy for him (in a few months) to say he loves you again).
I'm not saying either of these are the reason but whatever the reason you can work on it. Aslong as it isn't the "specific other woman reason" I think you can work through it because there is always a solution (for the other woman one you could try bigamy, but I personally think that is a silly solution).
When trying to get the information out of him remember not to show him your true intent why you want the information...
And also remember that you don't need to be in love to have a successful relationship with great sex...
And remember people can fall in love, and out of love, but they can also fall back in love!
try and find solutions until you BOTH think divorce is the best option.
and I repeat don't tell him your trying to find out the problem so you can create a solution, or that you want to make him fall back in love with you, don't tell him, you must keep these intents secret or he'll resist them.
Also try to get him to LUST after you again. It can't hurt, and you know how to make him do that ;) (and if you don't start another thread on the forum and ask).
And following out this advice in this post is the best shot I think you have of carrying on with him, I wish you luck.
remember lots of couples have the lust/love die from their relationships, its what people call "the honeymoon is over" this is when you both really crack down and see just how strong & great as people you really can be!