Not sure it's even worth it

I have been with my husband for 16 years, married for 11, and have never conceived. I know he has some issues with sperm production and the doctors say it is not likely that we will conceive without medical help, and that expense is not doable for us. So we have adopted two children through foster care. I'd still like more children and I know it's most likely never gonna happen but I still find myself hoping I'll get pregnant whenever my period is late. It doesn't help that my family keeps saying just wait it's gonna happen!  I mean don't you think it should have happened by now?  Why do I still hope, not sure why I even downloaded this app.