Should I just give up?

I am 45 (almost 46) and already have two kids born in my early to mid thirtieth. However, I would really want one more.. Both myself and my husband had all the tests done and everything is great. Had 3 iui and 1 ivf, all failed. I guess despite the great tests I can't beat the statistics and should just accept that this is it for us. We had tried on and off for 3 years and nothing. Never even got pregnant. I am just so tired and angry at myself for having waited this long...but mostly just tired...