Here's the thing Mane. We all are given a set of resources in different types of currency - time, money, emotional energy, physical energy and so on. If we start to overspend in one area, it usually starts spilling over and bankrupting other areas. Therefore, if someone is sucking an undue amount of emotional energy from me without any signs of the situation ever changing (temporary needs are one thing, ongoing with no intention/ability to change is another), then I need to draw way back. Otherwise, I run out of resources to care for the other people and obligations in my life that I am responsible for.
For most people, it takes awhile to learn at what point this is necessary, but I think the fact remains that for all people, there will be relationships at one time or another where it is necessary. I agree with Ginkgo that it is important to let people know why you are going, but it doesn't always mean that the going is negotiable. Hopefully efforts have been made before to amend the relationship, but sometimes if a pattern of one person doing an undue amount of adjusting giving, and the other person doing a lot of receiving while still maintaining decision making power in the relationship is just an unhealthy way to live.
I really can't comment on what happened with you and your wife, and I have no doubt that losing your son is searingly painful. I agree that if it's a marriage, you should be at least apprised of why it's over. However, the fact remains that whether you like it or not, your wife doesn't want to talk to you. Give her some space. If you are approaching it in the same way as you have here, I'm afraid you are likely to get similar results.
It's not really that the people here are entirely unsympathetic. It's just that there is frustration when:
1) Your purpose (other than fixing INFJs everywhere) is unclear.
2) You don't seem to be heeding numerous people who individually are expressing similar sentiments about the way you are approaching this issue. Take time to reconsider your approach and I really think more useful discussion for you will ensue.
3) You are new here, which means you will get a basic amount of respect, but don't hae a lot of collateral to fall back on if you are saying things that get people's backs up. Get to know some of us individually first and I think you will have better luck.