Oh lemon, you poor thing. Nobody should tell you to stop feeling sorry for yourself; it is quite natural that's how you're feeling.
However, I think you need a plan, just to give you some hope and something to work towards.
Were all the MCs naturally conceived pregnancies, or did you have fertility drugs? Has the consultant found anything 'wrong' with you? What options has he given you for the next stage?
I think you need to figure out what you could try next in terms of fertility treatment and perhaps explain to your DH that if nothing has worked in x months/years time, you really, really want to adopt and if you also have your 'miracle' then that's amazing but you aren't prepared to just hang around waiting for it.
Besides TTC things, have you got anything else going on in your life that you can look forward to? Maybe a big holiday, or something new at work, or a new hobby? Since starting TTC, I've moved house, started a distance learning degree and am planning a new career - I didn't expect any of these things, I expected a baby, but I'm really glad that I can look back on the past year and feel as though I've achieved something...could you do/think about something similar?
Also, look after yourself. A MC is a huge, terrible loss, especially having one at 20 weeks when I presume you thought everything was fine - so you should be grieving and giving yourself the time and space to do that. Big hugs to you.