Is it only that one alias that's not appearing, or is it everything in the file? Is this during login, any time you open a console, or what? Could you please explain step-by-step what you're doing and the results you get?
As mentioned, shells do not "remember" anything. Whenever any process closes, the environment that went with it gets deleted along with it. That's why you need configuration files like bashrc; to reload a default environment into a new shell when it starts.
So if your alias, or whatever, isn't available, it's either because the file itself isn't being loaded at start-up, or the contents are misconfigured in some way and some of the commands fail to execute properly.
As a quick test, try adding a line like
echo "~/.bashrc loaded" at the end. If it shows up in the terminal at start-up, then the file itself is loading properly.
Be aware that different configuration files are sometimes called for different shell instances. See the invocation section of the bash man page for more on which files get called in which circumstances.
Finally, did you see this section?
Code:
# Alias definitions.
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.
if [ -f ~/.bash_aliases ]; then
. ~/.bash_aliases
fi
The bashrc above is already set up to import (source) a list of aliases from a separate file, if it exists. So you might want to do what it suggests and put all your aliases in
~/.bash_aliases instead of the main file. Of course the importing will only be done if the bashrc gets exectuted, so make sure that's working first.