I thought it would just roll along once I actually managed to get one...
Nope. Also, I don't know what you're saying you want it to just "roll along to."
OP, romance is something personal, though our culture keeps trying to tell us it's something universal. Something you should have a good idea of before you get in relationships--whenever possible--is what the relationship constitutes. Just saying "okay, now more than just friends" doesn't mean anything, you know? If you mean "I just want someone to kiss on," then that's one thing, and if you mean "I just want someone to write romantic poetry to," that's another thing--and both of these can constitute relationships. Part of maturing into relationships is getting yourself a really clear idea of what you're looking for.
A lot of friction in relationships is caused by a lack of communication about what people want, often because they're feeling hopeful and they don't want to discover, right off the bat, that things won't work out for them. I've declined multiple men because I won't go out with someone who doesn't have any other friends, period. Another man I broke it off with because he was looking for a year of fun before going back to his old girlfriend, and I sincerely loved him. Another because we saw each other every day and he made his declaration via email. I've got little tolerance for cowards. Other women think they're cute. There is no formula to love but to love.
This isn't something where you need to find the right combination of behaviors, like the perfect key to a lock. You be you, and find someone who wants that, and who you also want. If you've got some unhealthy shit going on, then you should probably work on that--like, I dunno, being abusive or dishonest or manipulative. But otherwise, folks are diverse in their needs and desires, and that's part of the beauty of it.
If you want a girl, then you've got to know what that particular girl wants, and whether you sincerely want to be that person--or better yet, already are them. Not all women like muscly men. I, for example, prefer men on the androgynous/feminine side and find men who are into muscle-building a gigantic turn-off. You be the best you that you can be, and then worry about attracting the wimmenz.