Why am I being told I keep talkin to the wrong girls?

I meet a girl very rarely and the last 2 times they have both left me confused! im not one to date around so when I find a girl i like a relationship. Well my last 2 lets see the first one I met her at a weddining around mutal friends. She was older and had a kid. and a week later we started going at it and then became boyfriend and girlfriend, and outta nowhere she started actin all weird and I suspect but have no proof she was foolin around or left me for someoneelse. She denies it to this day. Anyhow the other girl I met was older and at a club through different mutual friends we met and next thing I know we started making out and a week later went out on a date and I come to findout she was a window! and started feelin all bad so she ended it!... anyways I am under the umption all girls are decent... so how am i talking to the wrong girls???