Hi, you will have these feeling for the rest of your life so just accept them as memories. The older you get the less important they will become. Dont let romantic feelings dominate your life as people will come and go. Just see these feelings as part of your lifes experience and be thankful you had the opportunity to share those times with him.
Make yourself the center as the bottom line is that only you can make yourself happy and dont count on others to fullfill your dreams.
You've been with your boyfriend for 7 years and you are still thinking about your ex? Hm.
What we do with ex's when this happens is fantasize about all their good qualities while minimizing their bad ones.
And then when we are dating something that we see something missing like a gentle side, an affectionate side, a sensitive side that we'd really like . . . then we should find a partner that has that. Don't settle out of fear of not finding the right person or leaving someone that is 'almost' but not quite the right person behind because what that really means is that even though they have good qualities, they're not a great match for you as you desire other things they don't offer.
So, move on. But it is odd to me that it's been SEVEN years. good luck