What message should I send when my ex-girlfriend is away from home?

Depends on your mood. If you still like her, you'd better keep her. Although I don't expect her to agree, at least I won't regret not saying such a thing.

If you don't like her, you can say some words of blessing, such as "be careful on the road and take good care of yourself when you arrive." Although I can't be your side to take care of you, I sincerely hope you are happy and healthy. " Although you are not lovers, you have been in love after all. If it weren't for the violent separation, I don't think it is necessary to have such a rigid relationship. Let's give each other a good memory, don't you think?