About 4 Years Ago I Had Laryngitis And Ever Since

About 4 years ago I had laryngitis and ever since I've always had chronic sore throats and a strained voice. I'm a singer and yes I sing a lot but my voice is pretty much always sore and it affects my sound most of the time too. Right now things have gotten really bad, I've been resting my voice but my range is still pretty much gone and it hurts a lot to sing. I went to an ENT doctor who looked at my vocal chords and said they didn't see anything wrong so what am I supposed to do now?