5 year relationship put the window losing hope on everything

I lost my son it will be a year in January. End of May I found out my boyfriend of 5 years cheated. I see everyone happy and having babies and I just wonder when will I find someone... I want that in my life and it breaks my heart that I lost all that. I’m in a relationship but it forsure won’t workout we’re just never on the same page etc so it makes me feel even shitty. Do I just let the right guy come in my life and not try to look for him? Just sucks