The warlock would get the benefits of bless
Bless (PHB, 219) does not have any restrictions other than the targets must creatures:
You bless up to three creatures of your choice within range.
They don't even have to be willing, so even if the Warlock didn't want the bless, they could still get and receive the benefits of the spell.
The warlock could refuse Guidance
On the other hand, Guidance (PHB, 248) does require a willing creature:
You touch one willing creature...
Guidance is also a concentration spell that only lasts 1 minute. So you can't actually have simultaneous guidance on multiple party members. You can cast it on one, and then either after the minute duration is up you can recast it on someone else, or recast on someone else under that minute and have it end on the original target. The spell also ends immediately after the next ability check.
However, if they did not refuse it, then they would still get the benefits of guidance as the spell has no restrictions or penalties and neither does the warlock class.
Party Cohesion and buff spells
Players are free to roleplay as they wish, but I'd talk with your table and DM about whether or not the party is supposed to be working with, against, or parallel to each other. Refusing to work together may be a symptom of My Guy Syndrome.
If you are going to 'flavor' your spell to be specifically a blessing from your god, then you and your table are going to need to reconcile what that means. It isn't something we can tell you, but please see the paragraph above about how your party works as a group.