Hello there
It's hard to break the cycle of negative thoughts. I'm going through the same myself at the moment and it feels very unnatural to me to feel worthy and speak to myself in a positive way. It's encouraging that you can understand it even for a short time and a small step in the right direction.
Maybe you could still volunteer for the time you are in Florida. I guess that any charitable work would be appreciated. Do you manage to get out of the apartment for some head space each day. Maybe just for a quick walk around the block and a change of scenery?
I don't know if it's any help but I've been repeating positive affirmations to myself when negative thoughts start to creep in. It takes a lot of hard work to unlearn patterns of learned behaviour and I hope you find the courage to keep going as you deserve to be happy.
Hugs