No.
How consistent would your character (you, yourself, in real life) be after saving your saviour from the claws of death, at the same time losing one of your best friends to some dude for a 2 year long torture session? I bet you'd be just the same person you were before. Totally consistent. Cause you know, consistency means character. (wtf)
And people learn things you know.
If she went through a dramatic character change in ME2, that'd be totally fine. The problem is, that she reverts to a lot of her ME1 personality in ME3. Her character is going zig-zag.
You can't go from loner civilian to badass commando in such a short time and without training. Liara goes through this sudden change even if she was never taken on a single mission in ME1.
Although tbh, her role as a combat squadmate made even less sense than Tali's in ME1. A civilian could not handle a real battle without training and intense psychological preparation.