First of all, thanks for the reply.

I probably should have mentioned that we did discuss his jealousy, but I simply didn't take it that seriously. He was definitely uneasy about it, but he also did not want to limit me (and himself, mostly) and seemed to care about the latter more. I also told him that the way things are now, I wouldn't cheat, so I guess that this is another reason why he might feel extra guilty now. Yet, we both agreed that it's essential to have freedom because we otherwise we feel sort of trapped.

I do agree that I shouldn't have dismissed his jealousy right away and should have done something about it, but I still do not understand why he felt the need to lie more than once. After the his first lie, we had a calm conversation in which I tried to explain that, despite getting mad about it initially, I would not mind if he cheated first because after all it's what we agreed on and he shouldn't feel guilty about it by any means. And all this time we have been together, I've been genuinely putting tons of effort to create a friendly and understanding atmosphere between us so that we would be able to share anything with each other. I guess I'm also disappointed because apparently he didn't feel secure enough to share in spite of those effors. I can't seem to get my head around why he wouldn't tell me the truth when I asked him explicitly in a nice way.

Also, I can't see how being scared justifies his attemp to encourage me to sleep with other people, which I did not want. His indecency in handling the whole situation is what makes me question the viability of this relationship the most.

I suppose that I should be having this conversation with him and I will as soon as I get hold of him. However, I still need an outside opinion in order to make an objective judgement.

Thank you very much for your answer, I really do appreciate your insight.