frustrated on another level

I have come to the conclusion that I won't become pregnant again 😔 after 4 miscarriages, then becoming pregnant with my little girl (who's 3 now), been trying for nearly 10 months and every time it's a negative test. I'm worried I won't ever be able to conceive. 
I am literally losing the will. I cry every month at the fact that it's taking more time than expected. 
I might as well just adopt another child or something. I feel like my partner will just up and leave as I know how much he wants another baby and we both don't want a too big age gap. 
I know I may sound selfish as there's women who are trying ttc for years which I don't mean to be selfish. 
I just give up with ttc. I really do 😭😭😭 please don't judge me I'm just frustrated and angryÂ