Hello dear, thanks for your question on HCM. I can understand your situation and problem. Honestly speaking pulmonary fibrosis and pulmonary hypertension are not good diseases to have. There is no cure because 100% effective drugs are not invented yet. Both if these cause extreme limitations of physical activity and shortness of breath on minimal exertion. Sex need a lot of exertion. So this will definitely creat problem. For your erectile problem, I advice you to replace tadalafil by sildenafil . Sildenafil is drug of choice for erectile dysfunction and also useful for pulmonary hypertension. So ask your pulmonologist to start sildenafil. Besides this, you should start low dose home oxygen therapy. Chest physiotherapy and deep breathing exercise are also good for you. All these will improve your lung function and decrease the symptoms.