If someone is making advances at you and you completely handle the situation... do you

I’ve been dealing with a couple of ex’s and some guys that have had “crushes” on me making bold moves lately. It’s seems that now that I’m engaged I get the: how did I let you slip away or the I’m sorry I never told you how I really felt stories. Even my son’s father that I was with for 8 years has been texting old family photos and pictures of us from when we first met. I’d never disrespect my guy. I either block, ignore or simply tell these men to back tf off. My question is do I tell my SO about these advances...or just keep it to myself.

I almost feel like if I tell him it will start problems...he’s been insecure in the past. 2 of the guys are my male friends that he previously warned me about the moment he met them. I was naive and didn’t see what he saw. 😫..help.