Well it sounds to me like shes not sure if she wants a serious relationship with you anymore... I mean especially since shes out there looking and actually went on a date with someone else!

First off, I wanna hear the story with you two... How old are you guys?
You say you have been living together for 5 yrs.....how long have you actually been together? Has marriage been discussed? Maybe she wants that and is trying to get you to commit further by dating this other guy.. I dunno...just a suggestion... Are there any kids?

Have things been rocky between the two of you for awhile? Have you noticed changes? I mean...if your in a solid relationship with someone, its kinda weird for them to suddenly out of the blue wanna date another person..

And um, that kinda sucks you two share a mortgage...and joint accounts without being married. IF you split up someones gonna get screwed....or at least the risk is there. Maybe she was expecting a further commitment like marriage...and when it didn't happen she realized she may never get that from you.....and is now out there looking for someone who does want that...

I seriously would get her to sit down and talk to you and explain why she wants to date other people.....and ask her how she truly feels about you. I mean she at least owes you that.... Maybe then you will begin to understand WHY...

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