PLZ NO JUDGMENT; HUSBAND TEXTING OTHER WOMEN?

I am 35 weeks pregnant. My husband and I have been married for nearly a year. 10 days before our wedding last year, I found out he had been texting a girl named Allie. They never met up in person (although he had invited her to a movie once) and never cheated physically. She contacted me because she thought I should know (even though she thought she was in love with him and it was hard for her as well). They had been talking for 5 months or so. At that point in time, we had been dating for 1 year, 4 months. Him and I talked it out, cried it out, and ultimately decided our marriage was worth saving. We even give advice to friends going through similar struggles. 

He always treats me amazingly, tells me how beautiful I am, kisses me goodbye in the morning, and spends as much time with me as possible (He's military so it's hard to get a ton of quality time).

Anyways, last night, I woke up because his phone was beeping. He got a text from a girl named Megan who he used to go to school with. I know he used to like her, but they've always had a platonic relationship as far as I know. She has a 3 year old son and just got unengaged. She was Facebook messaging him at nearly midnight (past midnight her time).

I went through his phone (I don't know what came over me as I've never done so before. Even when all the Allie stuff happened). 

He comforted her on her recent unengagement and how she was taking care of herself. Asked how her son was going and sent these messages calling her beautiful. He is naturally a flirt, but it made me uncomfortable. Especially because she sent him just a sad face last night and he last messages between them are from a month ago (leading me to believe there's some deleted).

So I went through his FB messenger...

... And found him talking to a girl named Audrey who I dislike because she called him a dumbass for getting me pregnant (we were TTC) and told him he shouldn't have gotten married so young that he's missing out on trying new experiences with other girls etc. Before this they were talking all the time and it was already bugging me. So he had promised not to text her ever again, showed me the deleted number, and I left it at that. That was 6-7 months ago. Their most recent messages are from February.(Notice he didn't text her, he fb messaged her. I assume to avoid pissing me off.) 

So I scroll down and find a message to a girl I don't know. Her name is Kaitlyn and in the past, I have asked about her when I've seen her name pop up. But I had assumed it was a Kaitlyn we mutually knew and he allowed me to believe that. Even bringing her up as the other friend... 

He does mention me in his text to her when she asks...so obviously she knows who I am. So maybe it's nothing?

Then, I found on his Facebook in his recent searches...the girl he was texting last year before we got married- Allie. There's no communication in his messages, no texts, and they aren't friends, but he obviously looked her up recently to maybe FB stalk. I texted her (like I said, she's the one who came clean last year and gave me her number to keep in touch just in case) and asked if she'd spoken to him lately, but no reply.

Finally, I found a text to his ex gf, Kim, that I've always been cool with (she's very supportive of our relationship from the outside, but has been known to be loose). I've been warned about her many times by his old friends and exes. There's nothing really there except that she's the only one in his texts (not messenger) with clearly deleted messages...like, all of them..

 What do I do? I thought we had the strongest relationship out of all our friends. Lately, we've been insanely happy. We currently have one of his friends who is getting a divorce living with us. This guy was texting other women, asking for nudes, etc and my husband was giving him relationship advice, even using the time he was unfaithful as an example for how things can work out if he changes and him and his wife build up new trust, like we did. 

Idk what to do. Being this far along in my pregnancy, I am extra hormonal. I am embarrassed that I was snooping through his phone so I don't want to bring it up if it is nothing. 

These texts are much milder than the ones with Allie last year so I wonder if it's just his flirty personality shining through. 

Sorry it's so long, it's just a really complicated situation with us in the military, me having a baby soon, and all of this mistrust floating around...