It's probably a little bit of both.
Being in love can be exhilarating. Having someone to confide in through life's ups and downs who is trustworthy makes one feel they are not "all alone". Emotional security is like having insurance. Having someone you can count on is liberating!
On the other hand being "in love" or in a relationship also means one has to be (considerate) of their mate. It's not all about "you" and what you want anymore! Some people find it very restrictive when they feel obligated to compromise or let their mate have their way on a particular occasion. Sharing is caring.
Relationships are more about "Us & We" not "You & Me".
Who you select for a mate has a lot to do with how free or restricting love is.
The goal is to find someone who shares your same values, wants the same things for the relationship, naturally agrees with you on how to obtain those things, and last but not least have a mutual depth of love and desire for one another.
Like attracts like in the long run and opposites attracts divorce attorneys!:)