I was only on hormonal bc for a few months before I decided I would rather do without because I couln't really tolerate it, and it took my body over three months before it started ovulating again, and even then the first few cycles were very sporadic (as in some anovulatory, some with ovulation). So, 15 years is a very long time in comparison to my few months.
Also, don't stress yourself out, stress will also influence your cycle. When I am under a lot of pressure my body occasionally simply gives up ovulating, even though I can clearly see the cervical fluid build up and that my body is trying.
And TTC in combination with thinking there might be something wrong because it hasn't happened yet is probably one of the worst kind of stress one can go through.
So, don't worry about it, I am sure you will be just fine!