1. Have an honest conversation with your parents.
Whether you choose to talk to them together or separately, having an intimate conversation where you tell your parents about the barriers you set is better than just assuming that they already know what's off-limits. If they don't agree with the boundaries because of their own personal reasons, thank them for their concern, then remind them that who you date is never up to them. Even if they think that it's not the best for you, they should trust that they raised you in being able to make good choices.
2. Don't hide your relationship to your parents.
While hiding your relationship looks like a better option than telling them the truth about dating someone that they don't approve of, it's better to be honest with them. Hiding it makes it more like you're doing something wrong, so being proud and showing them that you are happy with your partner could help them understand the boundaries that they should not cross.
3. Decide what's not okay to share.
As much as you must tell your parents about your relationship, there are still things that you and your partner should only be the one to know. From your arguments to your sexual intimacy, have some secrets so it does not become more of a bigger issue under the magnifying lens of your parents. In this way, your parents and partner would be more respectful towards each other.
When you establish boundaries, you must be able to adjust to your parents' wishes as well. This means you have to meet halfway. If they don't like you staying out too late with your partner, then respect that for safety reasons. Another tip is to let them have dinner with the two of you once in a while for them to get to know your partner more. Just figure out what you are willing to give to have a peaceful time with your partner since doing so gives you more control over the situation.
5. Stick to your boundaries.
When you establish boundaries, be sure that you can stick to them, which also means you have to calle them out if they cross the line, with due respect, of course. This is not the easiest thing to do, especially since it's with your parents whom you loved dearly. Believe us when we say that they will eventually realize that things aren't going to change just because they want to control your relationship. Soon, they will start respecting how you want to handle your relationship on your own.
As much as we grew up in a country that always puts family first over anything else, we also have to learn that whatever we do in our relationship should be our choice and our choice alone. As long as you're making decisions that wouldn't threaten your mental, emotional, and physical wellbeing, there's nothing wrong with wanting to be the one in control of this part of your life, so don't feel guilty about your boundaries!