Hi agrace, I used to hoard clothes for exactly the same reasons as you mentioned above until I went through the following experience two years ago. I'd like to apologise upfront that this isn't a light hearted post, but hope it may be another impetus for you to re-frame (for lack of a better term) those "excess but neccessary(?)" clothes in a different way that makes it easier for you to get rid of them with a clear conscience. OK, here goes....
When my mum died a couple of years ago, I was left to go through all of her clothes as my dad was too distraught to do so. After many months following her death, it was one of the last tasks left still to be completed. Dad really had tried to do the clean out many times, but just found it way too distressing. I ended up offering to do it for him as I guess I was made of "tougher stuff emotionally" so to speak.
I went in to her bedroom and opened her substantial wardrobe doors. Oh no. Mum had SO many clothes. Clothes from the 60's on. Piles and piles of clothes and that's not including shoes, bags and accessories. My mother had so many clothes that I would say that she wore probably 5 - 10% (max) of her wardrobe. The rest of the wardrobe was based on (I guess) either a "it will come back in fashion" rationale or would have to be a strong emotional attachment.
Agrace, it was to be blunt, a HORRIBLE experience! I honestly found this task more emotionally traumatic than planning and reading out the eulogy at her funeral. Yes, I am writing that very seriously - for me, it really was THAT BAD. I felt absolutely dreadful having to go through these mountains of clothes - afterall they still smelt like her; I could still picture her in some dresses and it ripped at my heart to have throw these items away (even if it was donating - it still was very hard).
This horrible experience was the catalyst for me to decide that I would not want my husband or children to EVER have to go through this much trauma (or at least, anymore than necessary) if I were to die unexpectedly. I felt it would be a really unfair thing to do to them - I mean, why would I possibly make them have to do something that could compound their grief when I could do it myself?
I went home that afternoon and purged my own bulging closet of all the suddenly seeming excess "carp". I cleaned and purged until I got rid of everything but the clothes and accessories I REALLY wore plus no more than three "sentimental" dresses. I made a decision that when I would buy something new from that point on, it would be on a "one in, one out" basis. This policy seems to work really well for me!
Once again, I'm sorry that this was probably heavy read. I just know that this is what helped me for once and for all overcome this issue. It also helped my best friend who was worse than my mum (seriously bad!) overcome this as well (I am so proud of her - and SHE feels so much better and has a great working wardrobe now! :-)).
I just thought maybe this story might also help you see things a little differently when you see all those little "extras". x