A word of warning. Online communications like this can foster a false sense of intimacy. It can be very intense and bypass a lot of the social rules present when getting to know someone in person. You will generate a whole lot of feelings and preconceptions in your head that may just not be present when you meet and spend time in real life. An example of this is when you say you feel like you know her a lot longer than you have. You don't, but you feel that way due to the intense nature of funnelling your communications down a very narrow medium. It's like those experiments where they get two people to think they've fallen in love by having them stare into each other's eyes and ask each other twenty very personal questions. It works the same way.
Be aware of this when you meet up, things may be quite different in terms of how you feel about each other, and you've got to be ready for that. Treat it as a first date where you know a lot about each other on paper, but it's not the same as the physicality of being there in person, and that you don't really know each other beyond what you've said to each other. You've presented yourself as you see yourself, but she may have different ideas (and so might you).
As for the ex, that's something to keep an eye on. People with kids come with a certain amount of baggage, and they know that it can scare people off. She may be bending the truth, but there's a bit of dishonesty there if she's telling you the ex is out of the picture while she's tagging him on Facebook. She may be trying to stop you feeling that your going to come in fourth place after herself, her kid, and the father of her child, but that may be the case. I know you said you have kids and are in contact with your ex, but have you felt the need to lie about it to this new woman? That's a warning sign if she's going to start a relationship by lying to you in order to manipulate how you feel about her.
