Most Helpful Guy
Keep this in mind: he was or still is hurting. It may not seem like it; but how a guy deals with a breakup ranges. Like one of the women said, it's quite likely he set you on the backburner while he was trying things out with someone new.
Yet again, he could be seeing another girl because he got the perspective you broke up with him, and its the only way he can see to move on. Aka the rebound girl. If you guys had a long relationship and it was at the "I love you" gooey stuff its highly unlikely those feelings just dissipated into thin air.
So like the below opinions, with time comes healing. It make seem like forever and yeah it hurts. It sucks. But you shouldn't feel like you're the only one who's hurting either. Either you are the dumpie or the one who was dumped, well you're both hurt. Always remember that.
There are also plenty of fish in the sea, and with time its very possible you'll find someone better than him.
Most Helpful Girl
She was in his life before the idea to take a break. Guys don't leave one option unless there is another option already lined up and guaranteed.
You have essentially been tricked into waiting for him to find out if this new girl will work out or not.
You need to cut him loose and move on. "The best way to get over someone, is to get under someone else."