If you start doing weird ass things you do not ordinarily do is a good sign of being in love. On the good side it can include writing poetry, writing good poetry, partying more, doing new things, have sex like greased pigs. But it is an emotional roller-coaster ride and there are moments of jealosy, fear of commitment, resisting temptations of non-commitment (how/why do the really hot girls always hit on you only when you have a steady girlfriend). It can be quite distracting from your personal and professional life.
There is also the kind of love only people who have been together awhile have. They have seperate lives, but sleep together and have sex but not every night together. They do girl/guys out with their female/male friends seperate from each other, and spend time with couples together. One cooks, the other takes care of the yard. One does the bookkeeping, the other sets the social calender.
The first paragraph describes me. The second a very close friend, who has a very good relationship with a pretty, hard working girl worthy of any man.