How do you deal with great friends with slightly negative energy/vibe?

I’ve been distant from some friends because of this and I sometimes feel terrible.

I’ve worked so hard to build a positive mindset and I’m not jeopardizing that for anyone.
Yet, I feel guilty.

As a single mom, I cannot afford to hang with you and go home grumpy. My boys will miss their singing and dancing queen too much.

Another friend said I probably feel guilty because I have a messiah complex towards those friends.

Maybe so. But what’s wrong with wanting to assist others?

I’m sad to be ‘leaving’ some friends behind and I wish we had matching vibes.

It just occurred to me that this thread is a goodbye. Cos how on earth do you tell a friend: Our vibes are out of sync, bye.?