I need advice

Hello everyone! So here’s the deal. I have three dogs, two are males (one intact) and I have a female (not spayed). I knew when we got our youngest, Finn, that we would definitely have to neuter him and he does have his neuter scheduled for the fifth. He’s a 3yo Rottweiler/ Border Collie/ Australian Shepherd mix and I’m honestly at a loss. I personally have put in so much work and effort to get him trained and out of the three dogs we own he’s had the most training; however, due to him being intact and him aging I feel that every year cycle my female goes through gets worse in terms of the roaming, aggression, and other behaviors such as not eating anything for days at a time (he’ll eat human food if hand fed, but will not touch his food bowl). His separation anxiety has always been severe and despite taking precautions, I feel that it’s just getting worse. Like I said we are getting him neutered on the fifth, there’s no negotiation there, but I guess I’m just worried that since we’ve waited so long to get it done that these behaviors won’t change. I also have a two year old at home so add the stress of that as well. I just feel like ever since I had my daughter, the dogs have taken a back burner and I do feel guilty and do try to spend time outside with the males specifically since they love to run and fetch, I just find myself always frustrated with the dogs. It doesn’t help that Finn consistently try’s to nip and rough house with the other male we have and Ducky my GSD mix is old and not having it. I just don’t know what to do anymore