Valentine's day isn't a religious festival ,
Does it matter? Christmas is only a religious festival if you want it to be. Most of it is just the midwinter party to celebrate getting past the darkest day of the year. Christianity just couldn't make the pagans stop partying so they tried to make it all about them (as usual). The point is that the year seems to be structured into "merch sales", some of which overlap.
- Jan 1st to Feb 14th - Valentines Day
- Feb 15th to Mar 30th Mothers Day UK
- Jan 1st to Apr 20th - Easter
- 21st April to 11th May - Mothers Day US to try and sell the stuff that didn't go on the UK mothers day
- 11th May to 15th June - Fathers Day.
- 16th June to 1st August - Festival of barbecues and summer
- 2nd August to December 24th - Christmas
- 1st September to 31st October - Halloween