if only they knew how awful this "cheating" makes us feel, they would have never ever done this.
You need so much better really, and you will have - a nice caring guy, who would worry about you, value your feelings, take care of you, and be for you a shoulder to lean on. Thats what you need. Your ex simply wasnt good enough for you, now you had a chance to see it.
Another thing I wanted to tell you - try getting back to real life as soon as possible. I know how it feels, that all you wanna do now is stay at home and cry, that you feel lost, lonely, abondoned. Thats not like that, thats just how it feels. Life if how you see it, really, so cheer up, turn on some music (i strongly suggest Lil Kim - some "feminine sht", nothing ever made we feel more confident in myself than that, and no other music cheered me more when i was worried about the relationship. No matter you like hip-hop or no, Lil Kim is the medicine for ladies with broken hearts). First, try to clean up in your head and heart. Thats difficult, but just move on. Thats all you can do now. The more you sit and cry, the more lost you get in this sorrow. Next time you will feel the tears in your throat, smile, turn the music on, go shopping, go out with girls, flirt, play, enjoy. This sorrow will leave you itself. And in some months you wont need him at all, and will be just grateful to the destiny you had a chance to see who he really is.
Take care, keep your head up gorgeous, you will have so much better.