I tend to view depression as an evolved adaptation and a certain state which it is natural for humans to move into in certain situations. I think that it can be helpful to recognize that dysphoria, sadness and grief are all natural reactions. It is ok to be sad. Although, like with all conditions if it becomes chronic or persists for an overly long time then you should probably get some help to deal with it. See here for more information.

For general advice for dealing with grief, see this article and apply whatever you think is applicable or would be helpful. Excerpt:

• Establish a simple routine
  • Regular meal and bed times
• Increase pleasant events
• Promote self-care activities
  • Regular medical check-ups
  • Daily exercise
  • Limited alcohol intake
• Provide information about grief and what to expect
  • Grief is unique and follows a wave-like pattern
  • Grief is not an illness with a prescribed cure
  • Children benefit from being included and learning that grief is a normal response to loss
• Compartmentalise worries
  • List the things that are worrying
  • Create a ‘to-do’ list, prioritise and tick off items as they are completed
  • Use different coloured folders for the paperwork that needs to be finalised
• Prepare to face new or difficult situations
  • Graded exposure to situations that are difficult or avoided
  • Plan for the ‘firsts’ such as the first anniversary of the death – How do you want it to be acknowledged? Who do you want to share it with?
  • Adopt a ‘trial and error’ approach; be prepared to try things more than once
• Challenge unhelpful thinking
  • Encourage identification of thoughts leading to feelings of guilt and anger
  • Gently ask the following questions – What would your loved one tell you to do if they were here now? What are the alternatives to what you thought? Where is the evidence for what you thought?

• Provide a structured decision-making framework to deal with difficult decisions e.g., When to sort through belongings? Whether to take off the wedding ring? Whether to move or not?

  • Base decisions on evidence, not emotions
  • Avoid making major, irreversible decisions for 12 months to prevent decisions being based on emotion
  • Identify the problem and possible solutions
  • List the positives and negatives for each potential solution
  • Determine the consequences for each solution – can they be lived with?

  I guess, and it sucks. I've been regretting not valuing him more during his peak health, as well, although maybe I'd always feel guilty for anything short of having been perfect.

I would try to stop doing this. It will gnaw at you and we can always find something that we could have done better in the past. The better thing to do is learn from the past, appreciate it and experience, to the utmost, what is happening now.