
Why were you prescribed Tamoxifen? It is an oestrogen suppressant. It is usually given to ladies following surgery.  The drug almost killed me  

Depression - can be hormone related. So we are more prone to it as we age.  Are you taking any medication for the depression?  I have taken various types of AD since the 1990s.
Breast pain can be hormone related.  Your scans show that there is no untoward disease.  I can understand the soya suggestion but organic milk and caffeine-free tea?  I would like to see the peer reviewed research on that one  
  
.  It is really Trial and Error ..... finding what suits us during the Journey.  
I used Valium: 5mg: on an 'as necessary' basis for many years.  My GP has more recently prescribed a beta-blocka which really really helps, it means that DH and I have a Life together again.  There is a 'test' which can determine how depressed a person is and whether ornot medication would help.
How about using the Valium - what doseage are you on -  regularlarly for 2/3 weeks?  1 tablet 3 times a day?  To see if it helps ease the symptoms and by how much?   Yoga can help anxiety as can swimming and brisk walking.
PMT can be eased by eating correctly - that is, every 3 hours.  Recommended by NAPS.