Think I was cucked by my ex, looking back at it all. Or was she just a cheater and I was naive? [cuckold perspective]

Disclaimer: I’d like honest feedback, I get it if you want to humiliate me that’s fine as long as I get honest opinions.

I started dating this girl a few years ago over summer but she ended things because she was going to work away for a year. That was kind of the deal when we first started things, and I accepted it mostly (I did a tiny bit of begging for her to try it long distance).
She broke up a few weeks before she was due to fly; but I still had her Snapchat. She’d gone to stay with her ex, and was posting snaps of her in his bed; her head on his stomach; and her in just a tshirt with him holding her with one arm around her.
This made me jealous, and I felt lied to but I moved on.

She came back just over a year later. She messaged me (I hadn’t been in any contact with her at all other than she sent me a picture of her and some friends on NYE by accident).
She wanted to start things back up, and to be honest I was still hung up on her so said yes immediately.
Not sure if this is relevant, but we’d meet up and she’d get me to go down on her; but then only give me a bit of a handjob or a blowjob – but never really got me to finish unless it was in my underwear. She didn’t want to rush to sex and that was fine with me.
Then she told me a guy in the same town, she’d dated for a while because she’d actually been back a couple months in the middle of her time away. I felt pretty jealous, and she told me he wasn’t that nice etc (but I later found out she introduced him to friends and family).
She told me he had nudes and videos of her on his computer, and he’d claimed to delete them but hadn’t. So she told me she asked to go over to delete them herself and if I was ok with that, I said yes and offered to come with her and wait outside but she said it’s fine.
She then text me the day she was going over that he said she had to watch a film before he’d let her delete them, which now I look back sounds weird, and at the time I didn’t like it at all.
6hours before I heard from her again, she stopped by on her way back, we hung out for a bit and I did ask why she took so long and apparently he couldn’t find the laptop. She was a bit of a mess but she didn’t look like she’d had sex, she explained she fell asleep during the film and that it wasn’t just him anyway his friend was there so nothing happened.

Then a year into relationship, she went out with some friends, and went missing for about 10hours. No one knew where she went, and everytime I asked she gave a different story.
I do know from a friend who saw her that she was hanging out with a group of guys we all used to go to school with but none of them were her ex.

We recently broke up, for various reasons.

Not sure if I’m being paranoid, but was I being cucked?