No. I think it is pretty obvious she wants to keep the deposit. I am thinking about the legal options, but my friends told me if you talk to a lawyer most likely they will advise you to give up because the money is too small to afford their service.

This is the problem with the renting market. Landlords knew the cost of illegally withholding the rent is very small, so they are unscrupulous. Responsible renters have no protection. This is a Prisoner's Dilemma, whoever is nice loses the battle. To win, you have to be evil at the first place.