YAY! It's Group Therapy Thursday time!

Dear Ted and Amy,
I am either losing my mind or my boyfriend is cheating so I'm hoping you can help me figure out which is happening. He and I live together and have a three year old. He works from home and I go into the office every day. He has enough time during the day to be the main caregiver while I'm gone so he's the only one there. But lately my child keeps talking about "Daddy's friend" that visits during the day. Naturally I asked my boyfriend what that's about. He immediately said it's just him but he reads our son stories and uses different voices so that must be who he's talking about. He even went off on the whole storyline that he created with this cast of characters so it sounds really sweet and that he puts a lot of effort into being a great dad. Here's the problem: my girlfriends are absolutely convinced that he's cheating and that this "friend" is not imaginary. Now I'm spiraling even though everything at home seems totally normal. He doesn't at all seem like he's hiding anything and he's very involved and present. He did cheat a couple of years ago when we first started dating, but things have been solid ever since. I don't want to ruin this whole relationship by accusing him and blowing up our whole world. How can I figure this out without sounding like a jealous girlfriend?

Signed,
Mystified in Minoa

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