I agree that happiness is not a permanent state to aim for. I think the absence of anxiety and a sense of purpose is my goal now after reading a good few books about happiness a while ago (Catherine Grey's ''The simple joy of the ordinary'' was my favourite, also liked Jonathan Rauch the Happiness Curve and Gretchin Rubin's The happiness project)
What I took/remember from these books
Hedonic adaptation , you hedonically adapt to what's good. So if you're berating yourself for your feelings because you have a good house, a good husband, lovely kids, don't, because you've adapted to that.
Values / Congruence. Go over what your values are and check that how you spend your time and how you live your life aligns with your values. eg, If you say you're creative but you never create anything then get the paints out. If you say you hate bullies then include the person most likely to be left out. If you value courage, go somewhere on your own and take a risk.
Free time- Pastimes shouldn't be all relaxing. Watching netflix and doing nothing at the weekend is a relief in the moment but leaves no sense of accomplishment so divide your freetime up. Get the sewing machine out, learn a language etc..
Socialising - it doesn't all have to be out to drink or to eat. It can be volunteering or debating, amatuer dramatics, art classes or mentoring. Volunteering obviously covers two categories.
Goals - aim towards something, but not necessarily in a work context. couch to 5k or learn to juggle.
Also give something back but only if it's a cause true to your heart, not for the sake of it.
I am lazy and I thought how can I combine all of these? A city walking tour combines walking (that contributes to well-being) and gives you knowledge about the history of the city and you get to talk to other people on the tour. So that combines three things that ............. well, if they don't make you happy, they will keep you busy enough not to think about being whether you're happy or not.
Good luck, and don't worry. It's all normal.
I'm practicing self-compassion atm and it's very good for acknowledging that life can be challenging, we all feel the same things and not every emotion is fact. Sometimes what we feel is just passing through.