African violet not growing

This once was a beautiful, thriving, African violet. It's been in th same place by the window since I've had it. It used to bloom flowers all the time. Then it suddenly stopped for a while. I thought it might be root bound since it was growing over the pit it was in so I reported it. It started to get blooms again. (I have consistently used African violet fertilizer as recommended.) Then the bigger leaves started to wilt and thin so I removed them. This picture is all that's left. I received it as a gift in the hospital when my baby was born so it's sentimental and I want it to thrive again. Please tell me what I'm doing wrong. I