Wonderful ideas & suggestions so far!
Sadness, anger & depression & all those other issues can totally be worked with EFT &/or TAT.
I actually started doing EFT because a friend lost her brother at a young age & she was devastated... I had to be strong for her, & after I discovered & printed out EFT & read the first part of the manual, I started applying it immediately. I misread the instructions & 'rubbed' the points instead of tapping, & did it over & over again, so I got EXCITED & had an immense amount of ENERGY (I felt almost guilty for feeling SO GOOD at the funeral!!) - but it was really important I stayed strong for her, & I did! (I had an aversion to going to funerals prior to that but going to this one was easy. I knew I had to be there & EFT helped A LOT!)
So I definitely don't recommend doing this before sleep!! (Tapping makes me a bit less but still over-excited too, pretend-tapping may be okay-ish before sleep, while TAT makes me pleasantly sleepy, & seems very much okay for before-sleep.)
However, it is important to understand the long-term reasons for depression & such.. A healthy nutrition & life-style including a daily walk in the fresh air (& possibly exercise) are a must, & EFT can help with motivation for that!
& if you're still feeling 'off' after a few rounds of EFT, check if you aren't hungry! (Or lacking B vitamins or Magnesium or something!)
Also, I had read about CBT (cognitive behavioural therapy) before, I highly recommend 'The Feeling Good Workbook' by Dr. David Burns, & I use de-negativizing, which is journalling after their method, to identify, challenge & get rid of negative thoughts - this can totally be done together with EFT!
The EFT & TAT newsletter & site give great suggestions how to 'tweak' the basic recipe & what to use it on...
As for marriage, communication & maintaining your level of energy without trying to get it from your partner, & speaking each other's 'languages of love' may be most important... So working on the communication skills (& again, a healthy lifestyle) seem essential - & they will help you in your biz life too!
EFT & TAT (www.tatlife.com) not only helped cure my car-driving, spider & dentist phobia, but also helped heal my relationship with my Dad that had long-standing resentments in it. Probably TAT was even more helpful for that. So were conversations with Dad. And understanding/learning what his work life involved.. But EFT & TAT really enabled a calm conversation with him..
What I mean is, EFT & TAT are just two helpful approaches, at times they might not be appropriate & something else may be more helpful, like going for a walk or taking a bath or clarifying a problem with someone... or doing some effective problem-solving or research on a 'problem'... But they can be of great help. If you do them.

Or tap on resistance to doing them instead.
