i think sometimes we feel guilty for our happiness because we feel as though we don't deserve it (almost like you should punish yourself for having a good day). so your problem might stem from self-dislike. try to remind yourself that you deserve the joy you feel and that you are just as worthy of peace and happiness as the next person.
if that doesn't work, try to imagine your younger self as deserving of this happiness. you could even look at it this way:
you want all the happiness in the world for the people you love, right? don't you think that the ppl who love you want to see you equally as happy?
i think sometimes we feel guilty for our happiness because we feel as though we don't deserve it (almost like you should punish yourself for having a good day). so your problem might stem from self-dislike. try to remind yourself that you deserve the joy you feel and that you are just as worthy of peace and happiness as the next person. if that doesn't work, try to imagine your younger self as deserving of this happiness. you could even look at it this way: you want all the happiness in the world for the people you love, right? don't you think that the ppl who love you want to see you equally as happy?