Formal:
* "À jamais dans mon cœur" - This is the most literal translation, meaning "forever in my heart." It's a very romantic and poetic expression.
* "Tu seras toujours dans mon cœur" - This means "You will always be in my heart," and is a slightly more personal expression than the previous one.
Informal:
* "Tu es toujours dans mon cœur" - This means "You are always in my heart" and is a more everyday way to say it.
* "Je t'aime toujours" - This means "I love you always" and can also convey the meaning of "always in my heart."
Poetic:
* "Ton souvenir restera gravé dans mon cœur" - This means "Your memory will be etched in my heart."
You can choose the phrase that best suits the context and your personal style.