As a background, I'm a 30 year old guy. About a year ago met a girl who's a couple of years younger. Both of us had broken up with our very long-term partners around a year earlier.
We started a casual relationship - we met up on most weekends, usually out for dinner or cinema and drinks. Sometimes we went shopping, watched dvd's... and every time we ended up sleeping together. We enjoyed each other's company and, obviously, the sex. But we were hardly ever in contact during the week. Just towards the end of the week we called or texted to agree what to do on the weekend. Sometimes we spent the whole weekend together, sometimes half of it, sometimes just an evening and the next morning. We never agreed anything long-term, didn't discuss our future, didn't discuss what kind of relationship we were actually having and whether we were seeing other people.
This went on for half a year. One weekend then I was busy so I didn't see her. On the following week I called her for weekend plans, and she told me that she had plans already, as she's SEEING SOMEONE. I was completely shocked and couldn't believe it. It turned out that she had met the guy some weeks before, and had gone on a date on the weekend I was busy. I tried to make her change her mind and spend the weekend with me, but no success. I felt like shit.
A month later she tells me that she dumped the guy, she misses me and wants to get back with me. I accepted, and for a couple of months now we've been together almost every day, like a regular couple, discussing future and all.
Later she also told me that she had also had a one-night-stand during my first spell with her.
Now I enjoy her company as much as ever, and I trust her, but my mind isn't at rest. I feel uneasy about these other guys having been in the picture, but I don't know if I can blame her. Clearly we weren't a couple at the time she met them. I had never even given her ANY indication that I actually wanted a proper relationship (neither had she).
So, is it just stupid jealousy what I'm feeling now... or is it something which is reasonable?
Thanks for reading, any views on the situation will be appreciated!