Late again!

So my last period was January the 14th, was due Feb the 18th and now I'm 35 days late. The period is January was the first in 4 months, saw various Drs and they've done a million and one tests and they constantly tell me there is nothing wrong and I should be getting periods. I get maybe 3 periods in a year and apparently that's normal and there is nothing wrong with me. I'm seriously getting upset about this now, I've had ultrasound scans that show no PCOS and my hormones are all fine, my thyroid is fine, my liver function is fine, my kidneys are fine, my gallbladder is fine, literally they cannot see why I'm not getting periods. Does anyone have any positive stories about getting pregnant when your cycle length is on average 108 days long? I sat in front of the mirror earlier and my stomach is bloated to hell and back and it's making me look pregnant, I constantly get asked when I'm due when my stomach bloats as well. It serious suck! Just want some positive stories!

Edit to add:

I'm seeing a Gynecologist to help with conceiving as that is all we have here in the UK. He has done naff all with helping, ordered bloods and a ultrasound, checked my partners sperm (which was above average) and has come to the conclusion that there is nothing wrong with me and I should be able to conceive pretty quick, yet my periods are really irregular.