If you really want to wait for marriage, then do so. Don't let this guy pressure you into doing something you don't want to do when you aren't ready. If he's worth it he won't pressure you and will wait. IT kind of sounds like he's saying he's not sure he wants to wait anymore, I think you need to talk this over with him instead of leaving it open to interpretation. Ask him if he seriously wants to go back on that decision, but make it clear you don't want to and are not ready to have sex even if he has changed his mind.
Do not give into him. If he's worth it, he'll wait until you're ready, or for marriage if thats when you really want to wait until.
If he's not prepared to, I'd say get out.
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