This guy is a classic stalker. The most important questions you asked are in your second-last paragraph. At this point it doesn't matter what sign he is. Please call your local women's support group or police, tell them that you are being stalked, and ask them the questions you asked here, in your second-last paragraph. If they ask you what he has been doing you can describe the texting and cyber-stalking and mention that he suggested that you ditch your kids to meet with him. This will be important information to the police or women's support when you ask for advice on dealing with him. On the other hand, you need not mention that he is a Leo. This is irrelevant to them and, sorry to say this, but mentioning astrology may damage your own credibility.
You mentioned that you are in the USA. Nearly every major city in the USA and some smaller towns now have women's support groups. Often they are maintained through the YWCA, and you can find them in the phone book. You may also be able to find them by calling 211, a number that has been assigned all over the USA to community information and support. (Other developed countries have similar support systems, through the police sex crimes division or through organizations similar to the American YWCA.)
Also, carry some pepper spray (legal in most states) or even mace (legal in some states) and learn some basic self-defense moves. (Gyms and police departments often offer classes.)
Congratulations on getting away from your previous abusive husband and on developing a sense of what sorts of behavior in a date signal future danger. Now it's time to talk to the professionals (police or women's support) and get some solid information on how to deal with stalkers. -- Joni