[header] How to be a supportive girlfriend [title] Recognize when something is bothering them. [step] You need to pay attention not only to their words but also to their attitude and body language. Be aware when something seems to be bothering them. 
[substeps] Try to avoid taking it personally when they are in a bad mood; chances are, it has nothing to do with you. Therefore, you should avoid making the situation worse by being rude or angry in return.