Feeling sad and depressed

So this month has been really hard. My boyfriend of over a year and I Broke up. We were talking about maybe being able to work it out. Then a few days later I have to quarantine because I tested positive for Covid-19 so I haven’t seen him. ( he is the type that has to constantly see you or he gets in his head) And then he starts talking to me as if there’s no chance of us getting back and something in me tells me he already had sex with someone else. Mind you we haven’t even been over for a month. And what sucks more is I really thought we’d be able to work things out. I’m confused as to what to do once I get to see him again and if he does tell me he hooked up with someone like how will I feel???? Going through a break up and having to isolate and be alone honestly sucks plus the whole Covid and feeling like crap. I feel depressed and I just want to talk to someone you know please guys any advice?