You spotlight the paradox between unconditional and conditional love.
Where's the line between being a good friend who's got a ready shoulder from time to time. When you lack any sense of being able to be positive - you feel safe telling them how you feel. And a friend who enables your focus on what's wrong (more than right) in life - all - the - time.
I have zero exceptions from folks. You be you. If the "you" you are - is 100% pessimistic 100% the time - great. Be that way. When you discover people who have a shred of optimism are missing from your circle - congrats on becoming aware of these missing souls.