If you have purchase details of your main account, Microsoft will give you your Minecraft account back, and allow for a password change. If it was done via PayPal or a Bank transfer, it's quite trackable, so it'll be easier to get it back. If it was done via a giftcard, like a redeem code, then give them the redeem code, and the email you used to sign up.
Hopefully this helps. Sorry to hear you lost your account :(