What are some things you do to make you more enthusiastic and excited about life?

Im struggling☹️☹️. Dealing with a bunch of problems and hardships, too many to put in here. Its affecting me at work. Im a Restaurant server. Some days i have great energy and chat well and smile with everyone, but recently its been dropping. Even if a coworker tells me something interesting, my mind is telling me to smile and be enthusiastic but i just cant. Im not the type to fake and sadly my emotions show on my face when i dont want them to. My energy is low, and i want to spread love and positivity but i just cant. Im still very nice tho. Never mean or rude to guests or coworkers. Any tips?