Not sure I’ll ever become a Mother…am I making a mistake?

So I’ve been with my boyfriend for over 5 years and we’ve been ttc for about 4 years with no luck…I did however find out recently what the issue might be and it can be corrected and I should be able to get pregnant…but here’s the heartbreaking part…I’ve decided to break things off with my boyfriend bc of multiple issues…mainly past cheating that I can’t seem to move on from as well as us just not getting along…I feel like I’ve lost myself and I’ve become so unhappy and depressed…I used to be so bubbly and happy all the time but not anymore…I want to get back to that…and I want to find someone who treats me right…I’ve never had that…I feel like I deserve that…I’m 38yo and the chances of me finding that person and him wanting to have a baby with me rather quickly are slim to none…I just feel like I’m getting to old and my chances are declining by the day just due to that alone…I just am losing hope that I’ll ever get to have a child of my own…and as heart wrenching as this decision has been I do think it’s the right one…it’s just been really hard trying to deal with all of this…am I about to make the biggest mistake of my life? Or am I making the right decision? I could use some advice ladies! Thanks so much!!!