Hello there! I am a 20-year old guy and I recently found out that my dad is jealous of my mom. They have been married for 20+ years and I am quite shocked to find out about this. Other people told me i should not be affected about these kinds of things, but i just want to help my dad overcome jealousy. I want my family to be happy.

So, a few months ago my grandmother passed away. A few days after that, the wife of one of our neighbors passed away too. Since then, my mom and my neightbor(mom-49, neighbor-over 55) have talked a little, mostly about funeral organization and stuff like that. Now, my mom is very religious and I dont think she would cheat on my dad. But my dad is obsessed with this and he got drunk 2 times this month because of it (which he mostly never does). He even found a way to record my mom and found that she said to someone: "we'll go for a walk tonight" (she was referring tk the neighbor). My dad also saw them one day walking together. 

Now, my mom doesnt have barely any friends, and i dont think that she likes the neighbor romantically, but how do i convince my dad of that? My dad is not very masculine (he is not the dominant one in the house) and i want to help him. I want to explain to him that jealousy is not healthy and he should be more masculine and continue to court my mom (my dad almost never takes my mom out if she doesnt suggest it). I hope nothing bad will happen and everything will come back to normal.

Has anyone been in this situation? Can you help me with some advice?

Thank you a lot!