It is hard to trust people in these crazy, convoluted times. On the one hand, you would hope someone you are this serious about would not pull anything to jeopardize your serious relationship. On the other, he is a younger man who are known, at times, to, well, not be so manly.
Also, you feel bad about yourself and possibly the relationship for even thinking this way for you start to feel like "is our relationship really as strong as I thought for me to not be as trusting as I thought I was?"
Ultimately, you need to discuss this with him, tell him how you feel, and if he respects it going forward, you have a keeper.
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