How do you get over insecurities?

It’s ruining my marriage and by that I mean it’s basically already ruined my marriage. I have been like this for a long time and ruined plenty of relationships over it. But now we have a baby due in two weeks so it’s a lot harder. I have borderline personality disorder, depression, social anxiety I am on medication I have done therapy no matter what I’m still like this. I try so hard to get over these feelings and if I keep my mouth shut then I’ll just bottle them all up and explode. Help 😞

I’ll add I’ve been in therapy a long time * years at that.