Hai Garg girl,
First of all i am impressed by seeing your true care for your friend. As a matter of policy a company the management takes these bond primarily to ensure availability of an individual, as u know that lot of resources are being devoted towards hiring the proper employees. whole of the efforts in term of physical as well as monetary are being wasted away once an employee leaves pre planned. so bond of short duration is ok and generally as a matter of terms some monetary pay-in is tied up for non compliance. Legally and morally speaking the right of company is intact, and company has all the right to sue for recovery of this damage. For this both the candidate and / or the surety can be sued.
However, from legal point of view, framing of contract is a specialized task and as u have not mentioned the details about the company possibilities are that some loop - hole must have been left in your favour, as most of the HR are not from Legal background. But taking this route is not advised due two reasons 1 . this is against the good faith, 2. as you have mentioned that the father may not be able to pay for the fees of lawyer and the other associated expense.
so suggested course of action is to take three pronged strategy i.e. 1. To apply for mercy petition with company management, even through union, if possible.
2. To persuade the in-laws to let the bride join back the company, informing them the probable consequences, as it is very difficult to make a carrier.
3. Request the transfer of the candidate to the location near to her in-laws if the company has any branch nearby.