I'm so sorry that you've been dealing with this on your own for so long! You are absolutely not alone. So many of our community members also struggle with IBS-C. I will link a couple of articles about it below, but we have many more on our website!
1) https://irritablebowelsyndrome.net/living/ibs-c-more-than-constipation; 2) https://irritablebowelsyndrome.net/living/chronic-constipation; 3)
https://irritablebowelsyndrome.net/living/ibs-c-more-than-constipation; 4) https://irritablebowelsyndrome.net/living/sudden-constipation; 5) https://irritablebowelsyndrome.net/living/constipation-battle; 6) https://irritablebowelsyndrome.net/living/summer-constipation.
And here are two articles talking about relief for IBS-C: 1) https://irritablebowelsyndrome.net/food/prebiotics-probiotics-constipation; 2) https://irritablebowelsyndrome.net/living/ibs-c-symptoms-try-mukhwas.
Getting doctors to listen to us is hard with both IBS-C and IBS-D. I have IBS-D and have never been taken seriously either, they just say that it's all in my head.
Have you had any luck with the Low FODMAP diet, keeping a food diary, probiotics, or even working with a dietitian? I've been seeing a dietitian recently and have found that to e much more helpful than the advice (or lack thereof) I've received from doctors in the past.
I really hope this helps. Wishing you all the best, Karina (team member)