Why Do I Feel Sad Leaving My Old Job?

So I left my first ever job. I worked at the same company and for most of it at the same location for almost 6 years. It was a toxic job and I didn't really find myself developing or getting stronger in myself after a while. It was for the best. I started working a second job 9 months ago and I finally left myong job for this one but I still feel so sad. It's a weird feeling. Getting comfortable and accepting a toxic job, making friends along the way and the predictability of the job. But it's sad too. You'll miss the comfort, some of the people, and aspects of it and the familiarity. One of my bosses was also a good mentor to me, and at this job I definitely had my share of ups and downs and highs and lows in 6 years. I think that's what kept me there so long. My newish job that I had as a second job for 9 months has become my main job now and I still feel like a fish out of water. Is this all normal?
Why Do I Feel Sad Leaving My Old Job?
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