I just found out my whole relationship was a lie?

Okay, so for three years I dated a guy. We first met when I was only 15 and he was my first true love. For 2 years, we were in a long distance relationship. We talked every single day for those 2 years... not one day ped when we didn't talk... our relationship was going great and I was head over heels over him. He told me that he loved me and that I was the only girl for him and that he could never imagine being with anyone else.. for 2 years, it went on like this. He seemed like the perfect guy for me. I never once cheated on him... or even considered it! I loved him and he told me he loved me. We even talked about getting married and what we would name our kids... he was also planning on moving back this spring... Then one day... i didnt hear from him.. his phone wasnt working and I had no way of contacting him... He wouldn't respond to my emails... Naturally, I got worried and decided to get into his email, which i've NEVER done before... I never felt the need to... I just wanted to see what was going on because I was worried... (I figured out his pword if your wondering how I got into his email.) I felt kinda bad snooping but I was just a worried gf! what I saw in his emails.. was heartbreaking... He had emails with girls, flirting and saying "i miss you" and all that. But that wasnt the worse part.. I saw emails between him and his best friend talking about how he was hooking up with so many girls and he would even go into detail as to what he did... I was devastated... I could not believe I had been so stupid... He finally decided to call back a week later... and I confronted him and asked him if he had ever cheated on me... He denied it until I told him I saw the emails... He finally confessed to having been cheating on me throughout the WHOLE relationship with many many many different girls but they meant nothing to him. He said he loved me and that i was his "main" girl... he just wanted "hoes" on the side... I absolutely could NOT believe what he just said to me... All i ever did was love him and be with him through everything... I was always by his side, always there for him... and then he also tells me that he got a girl PREGNANT and she was keeping the baby.... But he still wants to be with me... of course ITS OVER between us just to make that clear and I would NEVER go back to him... but I'm so torn right now... i cant believe there was a side to him I never knew about before.. he was such a good liar and knew exactly what to say... It's such a HUGE shock and what hurts the most is the fact that are entire relationship was a LIE... all those things he said to me were LIES... he hurt me so much... I wasted 3 years of my life thinking that he loved me... I don't understand why he would string me along all that time? Why would he bother keeping in touch with me EVERY SINGLE DAY... when obviously he had plenty of girls to talk to...?? I'm so heartbroken and I don't know how I'll ever get over it....