@rokuro
and I can see that you are a person that never takes circumstances into account
She is a servant nothing more nothing less she doesn't expect to be long enough in the life of Alejandro in order to make him happy that's why she is trying to make his childhood better in order for him to have a better life and we can't disregard the fact that they difference in standing is huge no one would accept a maid marrying into a Duke household
Also don't forget that she would have been the reason that someone else got fired simply because she talked to him while smiling
What you are expecting of her is not having fun with anyone except for the young master
Furthermore the stroy never implies she has feelings for Lorenzo
She didn't even blush once in front of him. All she is trying to be is a friendly co-worker
If you think girls fall in love with someone else only if that someone gives them some attention I would advise you to get some help for your trust issues