Shadows I could have written your post - it is such an awful situation to be in, I completely understand where you're coming from! It's like your heart is being ripped to shreds every single day...
I've just had my 4th mc and honestly don't know if I can go on ttc - the losses do not get any easier. But, like you said, you develop coping mechanisms that keep you going in spite of the world falling apart around you.
I find that work is helping me a lot - it gives me something to focus on and to get stuck in. There are lots of tight deadlines in my line of work, which do not allow any faffing about, and I find that this pressure really takes my mind of everything else.
Definitely savour those random moments of peace, where you can actually feel happiness. Very important! Your walk on the beach sounds lovely.
I have done various things to acknowledge my mcs - only to myself, really, it's not something I feel I want to share with anyone. I have planted a beautiful rose in my garden, for example, and one of the charms on my bracelet is for all the babies that I have lost. Things like that can be really helpful.
I am also currently thinking about getting counselling - just because I sometimes feel I am struggling to cope and that it is all getting on top of me.
I'd recommend to have a look on the SANDS website - there is a lot of useful information about pregnancy loss on there. For example, there are memorial services being run all over the country for people who have experienced miscarriages and still births, and I am wondering about maybe going to one at some point. I am not religious, but I don't think that they are only meant for people who are, it is aimed at everyone in our situation.
You are not alone. Have you ever mentioned your mcs to your friends or family? You might be surprised at how many will come back and say 'Yes, it happened to me, too'! I have been amazed at how many people have said this to me. Miscarriage is so so common, but no one talks about it.
Maybe taking a conscious break from it all could help? I had a few months off ttc after my third mc, while we were waiting for test results, and I found that such a relief. It is all-consuming and can take over your life. It might help you and your DP to touch base and figure out what you want to do next.
Sorry for the long post! Wishing you lots of strength for whatever you decide to do next.