As someone who had primary and secondary infertility secondary was FAR harder and I wish people would get over this 'you have one' thing, that's WHY its harder.
You can't live a childfree life, can't avoid the obvious triggers, you have your kid constantly asking why they dont have siblings like everyone else and everyone constantly belittles your struggle and tells you your 'ungrateful' and a 'bad parent' for wanting just a completely normal thing everyone else isn't judged for.
You have no way to protect yourself against the onslaught with secondary where as with primary you can carry on as always (holidays away, adult nights out, hobbies... your not spending your weekdays surrounded by pregnant people on the school run and your weekends at the park/softplay etc... every waking minute being reminded that your trapped in limbo).
I also hate the 'you're young'... fertility stuff is aimed at the older demographic, if I had a pound for everytime in the decade of trying a medical professional belittled my infertility by saying 'theres no rush your young' and sending me away I could have afforded IVF a lot sooner.
Yes I was young when I started trying in my teens, specifically because I DIDN'T want to be a 40 year old mam and knew given other in my family it could take a while but when you have had infertility for 13 years I dont want to here 'but your still young, you have time' because Im not yet 40, yes I also had time 13 years ago too and that all bloody ebbed away trying unsuccessfully.