How to get the character to the left of cursor in Visual Studio Extension?

I'm trying to get the character on the left of cursor. I've got the handler that intercepts the LineChanged event.

OnLineChanged(TextPoint startPoint, TextPoint endPoint, int Hint)

I couldn't find any built in method to get that from TextPoints.

What's the best way to do that?

Also, is there a way to check if the active window has IntelliSense window open? I want to abort the event handler execution if IntelliSense is open.

To get the character to the left of the EnvDTE.TextPoint:

string CharacterToTheLeft(EnvDTE.TextPoint p)
{
    EnvDTE.EditPoint editPoint = p.CreateEditPoint();
    editPoint.CharLeft();
    return editPoint.GetText(1);
}

To create an edit point at the current cursor position from EnvDTE.TextPoint startPoint:

    EnvDTE.TextSelection ts = startPoint.Parent.Selection;
    EnvDTE.EditPoint editPoint = ts.ActivePoint.CreateEditPoint();