Haven't spoke to her in a year. Why all of a sudden now?

My ex boyfriend dumped me a year ago someone else (january 2010)... His mom called me three weeks ago asking how i'm doing, i'm I still in school, how my kids doing and told me she miss my kids (we haven't seen eachother since janauary 2010). We talked like we were bestfriends again. A week afther that she text me...."I JUST WANNA LET YOU KNOW THAT I WISH YOU AND MY SON COULD HAVE MADE IT HAPPEN..." I replied "AWWW, THATS NICE BUT ME AND YOUR SON HAD ISSUES AND NEEDED TO GET OUR LIVES TOGETHER. ITS ALL GOOD THO, THINGS HAPPEN" and she never replied back! Three days later after the text she told me she found out her sons new girlfriend is cheating and he doesn't know it! She told me he's going to get it together and move it, he's bigger then that. 1.What did she call me out of the blue for? 2. Why did she send me that text? 3. Why did she call me to tell me whats going on with my ex boyfriend new girlfriend cheating? Why tell me their business? Explain in detail please!