I remember feeling exactly the same - stay in and you feel miserable and alone, go out and the same if not worse, because everyones, happy familly is right there in your face I live in a tourist area so really in my face -then the evenings the sounds and smells of everyones BBQ to which you didnt get invited, which hurts, but again,in my case, in truth I probably wouldnt have gone too if i had been.The hurt wasnt in not being invited but in them having one at all Life going on as normal for others while yours has crashed into pieces, is something some things including bank holidays become hammers smashing us even more.
The only comfort i can offer is that it bothers me much less now - After the first few, -rather than think of getting through it in negative terms -i earmarked things to do during it, got everything in i needed to do it -plus food etc so i didnt have to go out at all, then got on with it.garden or indoor DiY depending on the weather , -so I was too tired to care about anything social by evening.But then gradually, satisfaction at completing something became enough, rather than feeling i was misssing out on everyone elses happiness.
Winter ones are still bad -winter is bad full stop for me,but this last one i can even say i actually enjoyed.I did get a picnic with the grandkids -which of course is always a massive bonus -and by the river where we floated daffodils afte my husbands funeral - so i did think about him and wonder whether he would be sitting somewhere around, happy to watch them playing in the water too as he would have in this life,but it wasnt a sad or tearful thing, more comfoting thn anything else, and i enjoyed the time alone too just being in the garden with the birds. It takes time like everything else on this journey, they will never be the same, but heywill get better.