I'm tired!!!!!

I have been trying for a baby for a year now and nothing has happened. I'm so disappointed!!! Just got another BFN!!!! I have a blood disorder and will have to get a hysterectomy. So we wanted to try for his boy. My husband and I have two kids together and I have a child from a previous marriage. Never had problems in the past so I don't no what's going on. We I went to the doctor and had an ultrasound, he said everything was fine. He told me to start using opk and I did. This month I had 6 positive opk in a row...... not sure if that's a good or bad thing. Now AF will be here in three days, my temp is getting lower, and I'm just feeling so down right now. I'm so sick of trying. Maybe we are not suppose to have another child. I JUST DON'T KNOW ANYMORE!!!