Both parties should be considered equally guilty. The decision of walking down the aisle and saying "I do" for someone who lives in the US whilst taking the 'waiting period' too lightly is as stupid as it gets. It's not uncommon to hear about spouses living in Nepal having affairs or couples growing apart due to frustrations created due to uncertain waiting timeframe (A perm resident's spouse won't get her visa for 3-6 years while the timeframe for a Citizen can be 4-14 months). Hence, it's always best to sit down and weigh in on other available options - only getting engaged, applying for student visas first etc. 

On a different note, it could be worse - I've heard of Indian men who're already married in the US going to India to get hitched only for dowry. Hopefully, that's not a normal trend among Nepalese.