When your girlfriend says "we are not suitable" to you, it usually means that she has doubts or dissatisfaction with the relationship between you. At this time, how to respond appropriately is very critical. Here are some suggestions:

Keep calm. You may be surprised and disappointed when hearing news like this, but don't let your emotions control your behavior. Staying calm and rational will leave a better impression on the other person.

Respect her feelings. Even if you can't understand her thoughts, respect her choice. You can express your regrets, but don't try to force her to change her mind.

Third, try to communicate. Ask her for specific reasons and understand her concerns. Through communication, you may discover where the problems lie and have the opportunity to resolve them.

Fourth, show a mature attitude. Regardless of the final outcome, show maturity and generosity. This is not only a kind of demeanor, but also makes your image taller.

Finally, give yourself some time. Don't rush into a decision, give yourself some time to think and adjust. This time can be used to reflect on your performance in this relationship and to adjust your mentality.

In general, when your girlfriend says "we are not suitable", don't panic or give up easily. Through communication and understanding, you may find a way to solve your problem. Even if it's irreversible in the end, show maturity and generosity and allow yourself to grow in the relationship.