I'm flying over Christmas. 4 flights in total. A bit last-minute as the rules coming back home (from non-business trips) have only recently changed, and I won't have to quarantine anymore.
I would go, OP. I'm assuming your country of destination is like mine - you need to provide a negative test on entry, or take one straight away. If those you're seeing are fairly low-risk, and happy for you to go, I'd go. My mum just had Covid last month, my dad is a healthy 47 year old and my siblings are young and very low-risk. However, I'm not visiting elderly relatives, having a big family Christmas or mixing with other friends. It'll be low-key but that's how everything has been this year.
Flying is a very safe way to travel even during Covid. I've taken 18 flights since March, and I never felt safer. I am regularly tested at work (2-3 times per week), and since August also had tests before/after most flights. Not a single positive one.
Airlines won't let you fly without a properly fitted mask, and they don't tolerate any nonsense. I have seen a few cases where passengers were asked to get off the plane, unless their mask covered mouth AND nose. Funny how those saying 'but I can't breathe when it's over my nose' produced a variety of masks from their handbags in less than 5 seconds, when told that it was either the mask, or disembarking. If you're exempt, you provide a medical certificate stating so, and the airline tries to seat you in an empty area of the plane if possible.
I've only seen passengers trying to argue about the mask on flights to/from the UK btw. Everyone else seems to get on with it.
The planes are deep-cleaned much more often now, and have HEPA filters which means the risk of passing Covid to everyone on board is very low. Sure, if the person sat right next to you happens to be an asymptomatic, high-viral-load positive carrier, chances are you will catch it. But flights haven't ever been the source of a big outbreak. It's the lack of measures on them (back in Feb/Mar or even more important, people ignoring quarantine/testing on landing.
The airports are very quiet. They give you wipes and hand gel when you get on the plane. Again before a pre-packed lunch or a bottle of water or whatever. Ryanair don't spend the whole flight asking you if you want a drink, a cheese and ham panini, a bottle of perfume or some scratch cards. It's bliss.