Advise/Support PLEASE

I was in a 7 year relationship.. we broke up for 2 months..after a month he dated someone new for a month. we always had that connection. One day he texted me we start talking as friends he told me we was gonna get marry and grow old together. We decided we was gonna take it slow building our foundation stronger we was doing great. Now the other girl claims she is pregnant. What to I do it's crazy my whole world collapsed. A few years back I was trying to conceived. I couldn't. I feel so hurt now. I hate myself