I will second Sam's very good advice to seek God, and to find a counselor. This isn't a burden you need to carry by yourself...

...which I think you already know, since you are posting here, and you say you would like to tell your boyfriend too.

As far as the boyfriend goes, I say, give him the benefit of the doubt and tell him how you feel. If he were hurting, you'd want to be able to comfort him, right?--so give him the same opportunity to support you when you need it.
And, if he can't or won't step up to that plate, then better to know now than later. Yes, you are risking being hurt, but it is a worthwhile risk to take, IMO, that may save you some future heartache.

May I also add, please be patient with yourself.
Grief sets its own timetable, and six months is not a very long time at all to "get over" something as shocking and traumatic as suicide.
In some ways, you will never get over it completely, nor, in my opinion, would any caring friend. It will always hurt some. And that's okay. For myself, although it's been seven years, I still feel sad, and to be honest, a bit angry about the OD death of someone I knew.

...and that's okay. Remember the good and the bad together in life make us who we are.
This event will and has changed you and your life. And that takes some time to process.

So, don't feel you should have aready gotten over this. It's okay to still be sad or shocked or angry or confused or whatever.

And don't feel you have to go it alone.

You will be in my prayers also.

koalamom