Someone in Texas is logging into my Facebook?

[Altaf]

Do you use some proxy software to access the internet? If so, it is only you who are accessing your account from different locations. However, if you don't use proxies, it is suspicious. You say you have changed passwords and still having the same problem. This shows a possibility that there may be a spy software on your computer which is stealing your password and sending it to someone. Update your antivirus, install / update malware detection program and do a full scan.