be less cynical

So I tried not to be cynical about Valentine’s Day – not celebrating it this year but didn’t make any cutting remarks to others who were into it…..
That’s good – right?

So the real kiss of death for me in any relationship – and some friendships I’ve had – is when they look at me and tell me how cynical I am. Usually these are females making the observation.
Now the thing is I don’t think I’m particularly cynical but it is a constant pattern in my life. Maybe I should say I do think I’m cynical but I always think people who really know me understand I have this happy child under the cynicism – but maybe I hide that too well or maybe it isn’t there?
My trouble is I don’t know how to do this. Just not say some stuff out loud that I’m thinking? Not give the worst case possibility? Just be happy – what does that even mean?
Just pretend enough so no one notices?
What really bugs me enough to put this as a goal is that it really is the signal for a relationship being over. Of course I’ll still have failed relationships if I do this but at least they’ll be talking about something else. And I’m sick of knowing that hearing this means its over.
Any suggestions on how to do this?