This is some advice from Laural Scott ( Immigration Attorney who specializes in I-601 waivers) for writing your own hardship letter. I have copied it from www.immigrate2us.net
DO NOT OVERWHELM THE ADJUDICATOR WITH LOTS OF WEAK ARGUMENTS.
You want to give the adjudicator your strongest three to five arguments for hardship and PROVE your hardship with documentation. Don't 'bury' your stronger arguments among lots of weaker ones. Start with the strongest arguments first and include weaker ones later in the brief. Same thing with supporting documents. Support your points, but don't overwhelm. If you have a doctor's letter explaining your medical condition, you don't need 20 pages of lab reports.
SUPPORT YOUR ARGUMENTS WITH EVIDENCE
If you say your mom has a medical condition, supply a doctor's note. If you say you have unusual job skills specific to the US, get a letter from your employer. If you say your ex-wife would not allow you to take your mutual child abroad, get a letter from her if you can. Getting supporting documents can be a pain in the ###, but DO IT! If you ask the doctor for your records and he doesn't return your call, CALL AGAIN! If your mom's psychiatrist says he needs a release form from your mom, get her to sign one! If you're embarrased to tell your boss that the reason your performance has been slipping is because your wife was deported, bite the bullet and tell him and ask for a letter. Note: if you have a very strong argument, but you absolutely cannot get evidence - e.g. your spouse was the victim of a hate crime in her home country, but never reported it - include the argument anyway and give LOTS OF DETAILS. Telling a very detailed story with names and dates can sometimes substitute for lack of evidence if it is credible that no evidence would exist (e.g. you had a surgery ten years ago relavant to your current state of health, but the hopital has purged the records).
KNOW YOUR STRONGEST ARGUMENTS
Below are just examples of various arguments on a scale from 1 to 5, with 1 being the strongest and 5 the weakest. It is not an exhaustive list.
Level 1 arguments:
(a) you have a MAJOR medical condition (e.g. brain tumor, multiple sclerosis, cerebral palsy) which makes you unable to move abroad and for which you really need your spouse in the US to help take care of you,
(B) you are caring for an elderly, chronically ill, or disabled relative who needs constant care and whose condition is bad enough that you either MUST live with the relative or you MUST spend at least an hour a day assisting the relative with things like hygiene or physical therapy, and this makes you unable to move abroad and makes you really need your spouse in the US to help you care for your relative and manage your other responsibilities, or
© your spouse's country is in a state of war or major political upheaval (e.g. Liberia).
Level 2 arguments include:
(a) you are the primary caregiver for your child(ren) from a prior relationship and the child(ren)'s other parent will not allow you to take the children out of the country AND the child(ren) have formed an emotional attachment to your new spouse or fiance(e),
(B) you have a serious medical condition that makes it very difficult for you to move abroad and you need your spouse to come help you (e.g. you need to have major surgery sometime in the next year, with an expected recovery time of several months),
© you are caring for a moderately disabled relative who normally can care for him/herself but occasionaly has episodes in which he/she needs a lot of help from you and during those time you, in turn, need help from your spouse,
(d) a relative is unusually financially dependent on you (e.g. your mother has just gone through a nasty divorce with your father in which she got nothing and because she has never worked, she doesn't qualify for social security, so you are supporting her in the entirety for the rest of her life),
(e) you have a child that you are putting through college or are about to put through college, or
your spouse's country is on the verge of major political unrest (e.g. Boliva) or negative political change (e.g. Iran) or the country is known for oppression of one sort or another (e.g. you are a Christian woman and your husband is from Saudi Arabia), or it is in the infant stages of post-war recovery (e.g. Afghanistan).
Level 3 arguments include:
(a) you are the non-custodial parent of a child from a prior relationship and you have an actual relationship with that child and the child's other parent will not allow you to take the child out of the country but your spouse or fiance(e) does not have a relationship with the child at this time,
(B) you have a significant condition that makes it inconvenient for you to move out of the country (e.g. severe asthma and your spouse lives in Mexico City),
© you have been diagnosed by a licensed psychologist/psychiatrist with clinical depression due to your spouse's immigration problems (I've argued to the Administrative Appeals Unit that this condition should be taken more seriously by adjudications officers, but at this time I am listing it as a 'moderate' argument),
(d) you and your spouse have young children together or you have full custody of your child and can bring him/her abroad and your spouse's home country has bad public health conditions and bad public education,
(e) your job requires a license in both the US and abroad and it will be very difficult to get licensed abroad (e.g. attorney),
you have job skills that are very specific to the US (e.g. a tax accountant with extensive familiarity with US tax law),
(g) your spouse's country has a very bad economy (e.g. Chad),
(h) you have a close relative who is partially dependent on you financially (e.g. your mom gets social security but needs your extra $500 per month to stay in her present apartment) or physically (e.g. your mom pretty much gets around ok, but her health has been declining and you expect her to need more of your help in the near future).
Level 4 arguments include:
(a) you have debts you wouldn't be able to pay if you moved abroad,
(B) your spouse's country has a high unemployment rate,
© your spouse's country has a high crime rate,
(d) you've been depondent since your spouse left the country, but haven't sought professional help,
(e) your parents are getting old.
Level 5 arguments include:
(a) you got a high score on the Holmes-Rahe scale,
(B) you and your spouse want to have children in the future (but are not currently pregnant) and either the wife is getting older or the foreign country has a high infant mortality rate.
Don't get discouraged if all you have is two Level 3 arguments and a couple of Level 4 arguments. While one Level 3 argument by itself might not make a strong case, a few put together can be very strong in the aggregate. Just present your case in the strongest possible light. If all you can think of is a couple of Level 4 and Level 5 arguments, I recommend that you pay for a consultation with an attorney to at least see if you can brainstorm some stronger arguments.
Note: whenever you claim that a relative is dependent on you either for direct care or for money, you must explain why no other relative such as one of your siblings can provide the same care or support.