Thick discharge problems

Hi everybody! I'm 27 years and me and my boyfriend have been together going on 3 yrs and since we've been together I had this thick white discharge that's seems to never go away! And never changes consistency. It hasn't always been this way. I have 2 kids from a previous relationship 6 and 3 😍. But since we've been together I just can't seem to get my body back in tune the way it was before I got my mirena iud and it had it removed which was 2 yrs ago. The discharge is white and thick little to no odor. It doesn't come out it just sticks to the walls. I've been tested for std's negative for them all. I'm looking for some suggestions on how to get back to the normal clear discharge I was having before this became an issue!! Help please