Good job on all those positive changes. The period from 2-6 months can be very difficult due to continued brain healing. Difficulty with feelings and emotions especially. It is the toughest part of getting sober and is often referred to as The Wall in recovery circles. Sounds like you're in it. Sometimes we don't even know why our mood is bad so learning to identify my feelings (I was clueless before) really helped me.
Just stick it out, man - you're doing really great. Also, aerobic exercise is documented to be very good for brain healing.