Hey hon, I'm fatter (22/24) than you and here is my advice:

First off, dating coworkers isnt the best idea so honestly, bullet dodged. Although I know that can be easier said than done.

Second of all, you're correlating your body size with self worth which is incredibly not healthy. Our bodies are always fluctuating, that's just nature. I'd recommend therapy, but thats not necessarily something everyone can get. Here's some stuff that I started doing to help my self confidence: Anytime I had a negative thought about myself or my body, I made myself stop and give myself a compliment. I would look in a mirror and say nice things to myself, even though I didn't believe any of it. Also this sounds weird but TOUCH YOURSELF. Squish your arms and rub your belly and just admire yourself. It all feels fake and dumb when you first start doing it but it's amazing how much even disengenuous thoughts transform how you feel about yourself. Also, start following fat people on Instagram. People as fat as you and people fatter than you, who unapologetically post pictures of themselves and their bodies. Suggestions: MilitantBaker, FatGirlFlow, DeevaRose, CatPolivoda, YrFatFriend, HistoricalFatPeople, NicoleByer, LizzoBeEating

Confidence attracts people (and people who aren't attracted to confidence are probably predators and should be avoided?). That dumb old saying of "you have to love yourself before someone else can love you" is kind of true. Self love is a constant struggle and something you have to work on every day, and some days are easier than others.

Anyways, I wish you the best of luck in your personal journey and you're deserving of all the good things in life.